僕高卒だからそのぶん高校の問題とか出来る。

。

I only graduated high school, so at least I can handle high school-level problems.

Literal

I high-school-graduate [copula-だから] that-much high-school [possessive-の] problems [and-such-とか] can-do.

高卒 (こうそつ) is the abbreviation for 高校卒業 ('high school graduate'). そのぶん ('proportionally, to that extent') indicates a compensating advantage. The logic is self-deprecating but positive: 'my education stopped at high school, but that means I'm solid on high school material.' とか after 問題 softens with 'things like.' 出来る is the casual potential.