Removing a stud (or two) under a ceiling beam
Are these wall studs for your first floor?

If so then you need a proper header above the door and double up or triple the 2x6 studs on the outside of the door to support the header. The header should have 3 boards to accommodate the wall thickness. A 2x6 header is probably sufficient but I would go for 2x8 or 2x10 if it doesn't impede head clearance. Better to over-engineer than to under-engineer. Speaking of engineer, you may wish to consult with one.
It's looking more and more like a load-bearing wall. I don't think they double up the top plate for the fun of it when building a cosmetic wall.