Youtube can be chaotic but there are structured courses if you like that.
Otherwise online learning platforms works out well too. One example which I used previously was lynda. I have also bought the ebooks for my camera from Gary Friedman. That helped me a lot.
Another one which seems interesting but I haven't tried out would be the one from youtube channel but they have the structured course at sdp.io
Their free lightroom guides on youtube are pretty good so I assume the paid for course would be pretty good as well. Lightroom is a very simple program compared to photoshop so once you have your workflow in place you pretty much stick to it if you take a lot of pictures.