IMHO
The best starter kit is the RCBS Rockchucker Supreme Master Kit
You will need to add a few things for sure!
Die set of your choosing
Appropriate RCBS Shell Holder (they fit the hand priming tool in the kit)
A Dial Caliper
A case trimmer of your choosing Simple as Lee to fancy as a Giraud
You will need a work bench or temporary accommodation like a Black and Decker Work Mate
as you need a solid place to use the press.
Optional tools
The current kit comes with a Nosler Manual is not as good as some other. You will want other manuals to read and compare. The Hornady manual is great as it is fairly current and full of good information.
I advocate the use of a Vibratory Polisher for new reloaders. Keeps things simple.
Loading 223 you will probably encounter crimped primer pockets... so you will need something on simple like a deburring tool ( one is in the kit but it is hard to know how much to use it ) or Swaging Tool like a Press Mounted RCBS Primer Pocket Swager or a bench mounted Dillon Super Swage
There are some other case prep tools like a primer pocket uniformer and flash hole uniformer.
The biggest investment is for you to invest your time in reading the front portion of the reloading manual before do a darn thing. Do it several times!
There are great sources information out there. The RCBS web site, Sinclair International, and stay away from You Tube. Too MANY morons.
Do things right and you will have a smile on your face after your first test of your reloading skills!
Keep things simple! Build upon your success. If you go off on tangents right away it will confuse you and create detours.
Invest in yourself by reading quality material. One of the best manuals is the Lyman 50th. Especially for handgun cartridges.