OSDev.org

I'd like to make an o.s. in Fat32 because my father doesn't like me to have "diferent partitions" because of linux. can anyone help me?

ask santa a crash machine

more seriously, you can check Operating System Resource Center for some doc or declare your own filesystem within a huge FAT file (just make sure it's unfragmented at startup

Yes, but I can't stress too highly how incredibly dangerous it is to start using the harddrive on anything other than a test machine for writing your OS until you completely understand disk accessing and your disk driver is completely debugged.

I mention this because if you were at this stage you should already know you can use fat32 if you really want to.

Your father is likely to be less than impressed if you screw up his filesystem for good. At the very least limit yourself to read operations only, until you're confident you aren't going to screw up the filesystem structures writing back to disk.

A better solution might be to use one of the PC emulators (Eg http://bochs.sourceforge.net/) which will let you screw around with a simulated hard disk and let your father feel secure in the knowledge that you aren't going to trash the comp in the process.

Moral of the story: If you can't afford to lose it, don't gamble it