Than you x As you: Qual é o certo?

Hello guys, I was writing a comment on youtube when the following doubt came up (is it right? Can I use showed up?) in my head.

I'm going to try the same formation than you.
OR
I'm going to try the same formation as you.

I think the first one is correct but I'm not sure, So guys, Can you help me? Which one is correct? And Why?

Please if there is any mistake in the phrases above please tell me.

Thanks in advance!