What is preventing you from living peacefully?

If someone claims that ALL items are useful... well, excuse me. Such people should be isolated from society.

There are no absolutely useless subjects in school; there are just subjects that are not very useful.

And I really don't need algebra. At least because I don't understand it, and I won't. The delicate, creative soul of an artist and writer cannot grasp these crude mathematical formulas. I would rather study literature...
Nonsense.

Algebra is actually very useful, and everyone needs it. It is one of the most useful subjects in school, if not the most useful (along with language). It teaches you to think, and, most importantly, it is difficult to spoil it with a bad list of works, as is the case with literature, or with interpretations that cater to the current regime, as is the case with history. You are going to become a veterinarian, but how will you study and pass chemistry without algebra and accurate calculations (and it will also affect you in university)?
Of course, algebra is not interesting to everyone, but problems in mastering it within the school curriculum can arise only in three cases:
1. The person is completely lazy and does not try to understand anything.
2. The person experiences a strong aversion to the subject (most often due to the (self-)belief that their "delicate, creative soul of an artist and writer cannot grasp these crude mathematical formulas," which is related to previous failures. Sometimes the teachers are to blame. But the essence is the same: the person is lazy and makes excuses).
3. The person is an idiot.
However, the above applies to all subjects. There is NOTHING difficult in the school curriculum. If you have other interests, get your legitimate 3-4 (grades) and don't pay attention to them. Grades are definitely not the most important thing.