The premise is fairly generic, but there's definitely a thoughtfulness to the execution. The MC has a lot going for him, but he rightfully has had limited opportunity to learn properly, mostly self-studying as a result of him hiding his abilities, and as such he was able to be taken down by his opponent because of the skill difference, even if his raw abilities are much higher. It's nice that he's not just immediately strong and capable, but heavily limited by his circumstances in a way that still gives him room to grow and develop, as well as giving him a good reason to attend a school to finally become familiar with magic. A lot of power-hiding fantasies will just give their MC access to everything off the bat, which makes a school setting kind of pointless and bland beyond being an opportunity for them to show off, but here it actually makes sense as his magical literacy is limited enough where that sort of education would greatly benefit him.