Look around the room you are in. Count the things you actually picked.
For most people it is three or four. The rest arrived. A hand-me-down. A thing that was on sale. Something that came with the apartment and never left.
A room full of accidents will always feel like somebody else's room.
You do not fix that with a renovation. You fix it one chosen thing at a time.
One room, one corner
Not the house. One corner you see every single day. Coffee spot, the chair by the window, the side of the bed you wake up on. Make that one square agree with you and it changes the whole room's story.
Take one thing out
Before you add anything. Every room has one object you have quietly disliked for a year. Remove it. The space it leaves is the point.
Fix the light before you buy anything
Overhead light flattens a room and makes everything in it look cheaper than it is. Two lamps at eye level will do more for a space than most furniture. This is the cheapest change with the biggest return, and almost nobody makes it first.
Buy slow, buy once
One good thing beats four filler things. Filler is what you buy when you are trying to finish a room by Friday. Nothing has to be finished by Friday.
Put something living in it
One plant. A real one. It is the only object in your house that responds to whether you are paying attention.