how to reset iPad mini without computer

I need to do a factory reset on my ipad mini & I don't have access to a computer to connect to iTunes & for some reason when I put in the reset code on my device it's saying it's incorrect. Plus I noticed my restrictions options are turned on & I don't know what the passcode for that is either. I find it very weird that restrictions are turned on,when I never turned them on.

Can you please tell me how do I fix this?