It's not the little nemo movie I don't THINK. I'm fairly certain the movie I'm talking about was live action / cartoon. This kid goes to sleep (live action) then his bed comes to "life" and flys off (cartoon "dream land" ) and he is taken into this fantasy world and there's numbers and letters I think.. and he's on some sort of missioin. I can't rember if it was an educational film or if it was a feature film. The only thing I think of when I think of this is Fantasia? But I don't think that's right..

Only flying bed I can think of was Bedknobs and Broomsticks, it was live action /cartoon.

Little Nemo Adventures in Slumberland?

Any chance it might be The Phantom Tollbooth?

Its beadknobs and broomsticks

I mean BEDKNOBS and broomsticks