Hello, I have just received a student visa to study in Prague. On top of it where it says 'valid for CZE + STATY SCHENGENU', and D+C/VP/24/–/ in the remarks. What does this all mean? Thank you!

It means that the visa is valid to travel wthin the Schengen area during the first 3 months after your arrival in the Schengen area.

Then it allows you only to stay in the teritory of Czech republic, until you get a residence permit.

When you receive a residence permit, you'll be allowed to travel again within the Schengen area.