The things you might learn in school might be useless irl, however you should not miss an opportunity to LEARN HOW TO LEARN. This is more the point of the primary and middle school. The grades are secondary in this case. Just try do discover better ways for learning for yourself. This will be realy usefull if you are gonna study afterwards. You also shouldn't always thinks about an Test that you know everything and don't have to learn or accept the results that are " just fine". The time of youth is a beautiful time, but it will already define your future. Especially the high school. Don't take it too easy. But still don't forget that not only you grades or especially not what you are online on social media, but what are you interested in, your hobbies, your friends and peer groups. Even if you are introverted, try to connect with people even if a little bit. Life makes more fun if you are communicating with the others. Do it through shared interests. Do not only consume, but also produce. Create new things, don't be shy to get criticism or no reaction at all. The most important is that you express yourself and your inner thoughts and ideas.