how do i reset macbook pro a1286
I WANT TO UPGRADE MACBOOK PRO A1286, FIRST I NEED TO DELETE EVERY THING.
Make sure you have a good backup before you start. Then follow the directions here to do a factory reset.
What to do before you sell or give away your Mac - Apple Support
This will install the original OS your Mac shipped with. After that you can upgrade to the latest OS your Mac is capable of running.