i remember a long time ago i used to watch this anime on TV
its about a boy with a alien?

Description of the Alien:
the alien can change into different things, like one time a scooter that can go
either really fast or really slow
-the alien im pretty sure has like spikes on his head
-he is like blueish-green

one episode shows this guy trapped in time, with bunch of stairs,
another episode shows them "wearing other people"
as in you're wearing someone els skin, and they were taking them off, zipper on the back

thats pretty much all i could remeber

I cant remember anything like that buy maybe more info would help, like... is the alien anthromorphic or like an animal? Is it horror? comedy? And what do you mean by "them"? the boy and the alien or are there several aliens?

its mainly comedy, its a little like doraemon and they seem to be in elementry school
the main boy i think has a crush on a pink hair

bump

I remember that! I think...it definately rings bells...did the kid have a large mixed gender group of friends?

Also what country was it aired in (which country did you watch it on tv in), about what time period and if you have an idea of the channel that would also be useful. Even if you don't specifically know the channel there were likely a few channels you frequently watched so if you narrow it down there's a higher chance of finding it.