Quoted:
Forget it. Ask for advice, get criticism.
My poor mangina got sand in it.....
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We are trying to help. In particular, we are trying to prevent your second floor from collapsing when any kind of load is put on it.
You need to figure out your loading and then consult a span table to find out what size you need to span however long.
I recently nailed and glued 4 2x12's to make a beam to span 11 feet. It is support by 8"x6" posts at each end. And, that was really at the limits.
You will probably need to at least use a gluelam or LVL beam for the header supporting the joists.