Lack of time to complete the courses

I am currently looking for a React course, some courses are upwards of 40 hours and it is too much for me and I am busy with work I want to learn from another source but I’m afraid it won’t be as useful as Udemy courses, Isn’t it a problem if I look at youtube or another source?

I already bought a Javascript course from Udemy which was 60 hours up and I finished the course, it was really useful but I don’t have the time and I get bored soon when they give too long to the courses, I want to try other sources like YouTube.

Sorry for my English.