Upvote:4
You have to apply for a Schengen visa from the country which is the main one in your visit, mostly the one you stay the longest. Only if you do not have one of those you need to apply in the first one you enter.
I bet your reason to go to Prague is more than a few hours sight seeing. So you would need to apply at the Czechia embassy or consulate, or from whomever handles their visa for the area you live.