Is the wheel secured with nuts, a skewer, or something else?
Nuts need a spanner. A skewer is usually quick-release (lever cam) but may need an allen key. There may even be Allen key bolts but less likely. Some QRs have a lever that can be removed for security, these aren't very common either.
If the bike has rear-facing drop-outs there is probably another bolt you need to undo; this is the case for most fixed-gear bikes, some single-speeds and bikes with hub gears. (E.g. Sturmey-Archer 3 speed.)
Webstes such as Sheldon Brown and Park Tools have useful instructions on how to do most things to most types of bikes.
Lets look at this question with all the given information:
His handle is crazy bmx,
the wheel won't come out,
He has a tyre,
He sounds young.
only 1 post, probably can't find it again to reply to our questions.
I am suggestion it is a BMX and he needs to break the chain to remove the wheel. It may have a split link, a soft link or just need a chain tool to remove the wheel.
One question not discussed: Does the wheel really want to be removed??