Are you weighting yourself first thing every morning and are you doing so fasted and dry (before you shower, eat or drink and after you've used the bathroom)?
To appropriately track your weight you need weekly averages and each weeks average should be from weight ins that you do as described above. You take Week 1's average and then compare it to Week 2's average. This is important, because hormone fluctuations, daily differences in hydration, and so forth are going to cause your weight to flux up and down so taking a weight in from just one day and comparing it to another is pretty much useless for measurement.
Are you tracking your food? You should have the full MyFitnessPal App, the paid version. Everything you consume should be tracked so that you hit the within 50 calories your goal every day or within 5 grams of your macro goals each day. I am a firm believer in macronutrient tracking, at your weight and health condition I highly recommend you hire a nutrition coach to help you set those, adjust those as needed, and to hold you accountable.
Also, you shouldn't be crash dieting man. A big rookie mistake is to do a drastic cut of calories right off the bat. The wiser way to go is to for the first week or two figure out what your maintenance requirement is for a healthy macronutrient balance. You would be surprised how full some guys feels when they do that, because they're not used to eating low fat and high protein with the right amount of carbs. When you eat low fat suddenly to meet protein and in particular carb goals you're finding yourself eating a lot of actually very filling food, because fat is dense in calories and you're used to consuming so much fat. Once you're balanced at sustainment than you make gradual cuts in total calories down adjusting to put you on track to a conservative and consistent weekly weight loss (see my notes above about how to weight yourself).
The other rookie mistake is to hammer yourself in the gym right off the bat like you are David Goggins, don't do that. Your body is overweight, but you're most likely not consuming the proper nutrients and your skeletal frame is under a lot of force man so you need to get set-up for easing your body into a weight lifting and cardio routine it can handle (low impact cardio that's not crushing your joints and bones). We want you to avoid injury and be consistent not act like you're doing the fat man's version of B.U.D.S. Hell Week.
It's time to spend money on a reputable personal trainer man, of all the money you spend that and the nutrition coach will be the best money you'll ever spend in your life.
Medically, I hope you're working with your doctor. You really need to be VERY careful about that blood pressure issue. You should really be checking to see if you can get an echo cardiogram and really dig into seeing if you've already developed a blockage of some type that is the cause of that high blood pressure. You could be very close to a heart attack and unfortunately at this point exercise could actually cause you to have a heart attack so you need to get medically cleared before starting any exercise regiment (that's not joke and should be job 1 for you before anything else). You may need to be put on cholesterol meds or take other actions. Make damn certain you're seeing to that, because believe me nothing is more important than good medical health so put any pride or "I hate doctor's offices" bullshit aside, because this is your life brother.
Your doctor may want you to only do cardio that is monitored at a cardio rehab hospital facility by professionals who will monitor your heart rate and blood pressure during your exercise. Some better insurance plans will cover that and some will not, some will cover so many sessions, but you need to look into that. Doctors are always going to err on the side of caution, but you better damn well listen to them because there is a reason they do so. If your doctor isn't cool with you exercising outside of a hospital right now than you need to workout how to workout under hospital supervision.
Also, this is life now man. Being healthy is life now, I mean like a Mandalorian "This is the Way." Every day, forever. This isn't a 12 weeks and I'm back to eating how I want and living like I used to thing. This is a new you and a new way of focusing on health above everything else. That is going to require a change in your mental and spiritual self man. You need to be dedicating time and effort to every day doing something to address your mental health like it's a workout routine in and of itself. You need to do something to melt the stress that you've packed on to your brain over the day otherwise that stress will build up and it will sabotage you. Negative people and temptations need to be avoided at all costs. You need zen man, you need to get right in terms of spiritual balance. What that looks like depends on the individuals. For some guys it's taking a daily walk by themselves for others it might be fishing daily at a pond for an hour, maybe it's meditation or just a relaxing drive in the countryside with the top down on a convertible or on your motorcycle, whatever man...make it a daily thing. So many men neglect that, they view things in isolation when everything is connected and your psychological health is definitely connected to your physical in equal balance each feeding the other.
Men have been conditioned to be work horses in our society. Your employer and even your wife and kids will work you and drain you of everything you've got if you let them. You can't be afraid to be selfish and take some time for "you" every single day. This is a loss of air pressure in the plane situation where you need to have your mask on first before you help anyone else or you'll pass out and will not be able to help them anyways. Don't allow yourself to be ground into dust literally. Temptation is everywhere too, society will stress you out and then offer you the most unhealthy horrible shit to provide temporary relief at a cost. It's a daily fight against that shit man and it's the number one fight we all need to engage in for better health.