Been having the same problem while purchasing a new house.

Been having the same problem while purchasing a new house. I and my wife been working a good amount of time to save up for a new place to live however our budget wasn’t so high, so we got a little place that hasn’t been looked out after. Considering we spent all our money we decided to do the repairs by ourselves and the biggest problem we found was to fix the subfloor within the bathroom doors. Thankful there are companies such as https://doordesignlab.com/interior-doors/finish/pre-finished.html that can help peoples in our situation. They have amazing CS and professional, fun and outgoing staff, I would highly recommend it to anyone that went through the same problems as we did

I think you need to call a master

I want to install a 32-inch door (I have a stove) in this 36-inch opening between the finished basement hallway and the unfinished furnace room. So I think I'll frame the doorway by adding a couple of king studs to narrow the frame. I understand that I will need to nail some plantar plates to the concrete floor and then use my foot to nail the studs to the plantar plates and head plates.

The problem is that the existing basement floor seems to run halfway through the doorway. I think it's plywood or OSB over DMX. So I'm not sure if I should a) try to remove the subfloor along the way, or B) try to frame the floor. If a, should I try cutting in place or do I need to remove most of the floor base and re-install it on the wall? If b) do I cut my plantar plates half the width and apply them to the base of the floor? Or should I just cut a 1x1 notch at the end of the stud and then run that stud straight from the concrete floor to the top slab?

Photos are attached. I really hope you get this, and thank you for your help!