Well I be able to convert this to a storage space safely?

Have some space above a section of my garage – approx 9 X 18 ft.
I want to put some OSB down and install a ladder so that I can use it for season storage.
After some research is seems anything with 2X6 or 2X8 is not suitable for weight bearing, but this seems to be livable space, which is NOT what I’m doing. I expect to store my riding gear, saws, paint stuff, sports things, etc.
If I lay 1/2 inch OSB, would this be acceptable and what kind of weight bearing can I expect. Would I be able to walk on it without the whole things collapsing?