Is it possible to submit transcripts from multiple schools?

I moved after 6th grade so I have been in 2 schools in middle school. Is it necessary to submit transcripts from both schools?

I am pretty sure the AOs will want both schools’ transcripts

It depends upon the school to which you are applying. If the school asks for transcripts from 6th grade on, yes. If they only ask for 7th grade on, then no.