Do i need a permit to fix a house?
It sounds like you are doing something substantial. Any permanent change to the house requires a permit and possibly a CO. If u make an addition to the existing structure, I suggest you get approval before you start.
not if u own the house
It all depends on the projects that you want to do.
what are you wanting to do?
Depends on what you want to do and what jurisdiction you are in. Some places require a permit to change a light fixture others don't. Check with your local permit office.