General courses teach you to talk about the weather and your family. If you already spend hours a week on cooking, football, gardening or a video game, that material is better — you have the background knowledge, the motivation and a reason to come back tomorrow.
You already know what they are talking about
Comprehension depends enormously on knowing the subject. A cooking video in a language you barely speak is followable because you can see the pan and you know what happens next. That familiar context does the work a textbook tries to do with glossaries, and it does it faster and without effort.
The vocabulary is narrow and repeats
Any specialised field runs on a few hundred terms that come round constantly. Ten videos about the same hobby will drill that set harder than any list. It is also vocabulary you will actually use, because you will keep talking about this thing for the rest of your life.
Switch the input, keep the activity
Do not add language study to your week. Take something already in it and move it: follow the same sport in the target language, watch recipes in it, join a forum or a group chat about it. The habit is already built. You are changing its language, which is a much smaller ask than creating a new habit.
Expect a rough first month
You will understand less than you are used to, and that is uncomfortable in a thing you do for pleasure. Accept a temporary drop in enjoyment. After a few weeks the specialised words settle and the material becomes comfortable again — except now it is also practice.
Pick the thing you would be doing anyway and run it in the target language. It is the only study plan that competes with your own interests instead of losing to them.