Is it normal that i cannot tolerate doing something that's useless

To be fair to make digital art you must understand physical art. Some artists use 3D dummys to understanding shadow and shading. So knowing different forms of art is always helpful. As far as having useless classes in your degree that is kind of an issue we have in general with the HS and university set up. I would look into a ACS degree set up as there are degree set ups which are more focused, shorter and give you an internship and lets yiu transfer directly to field you are studying. Also art like this can be done freelance so I would if you could learn what you need and just drop out.

If you have the chance please visit the Milwaukee Art Museum... especially the sections on modern art.

You are likely going to be very surprised at what can be used to create art.

Bonus is that the relatively new entrance building is in itself a piece of art and you can spend hours looking at it and watching it's "wings" rise and fall during the day.

Its a very rare modern example where an architect was allowed to completely build their vision on what a building would be; and not start with and idea and then cheapen it along the way because the idea cost more to build than anticipated: Milwaukee just kept coming up with the money to implement every idea and concept despite it costing about twice what the initial guesstimate to build.

The architect has never had another of his buildings finished that way. Everyone else didn't have the budget to finish his concepts... and things were cut out as the building progressed.

https://mam.org/info/architecture.php