I think it's good to practice human anatomy regularly, a lot of the information carries over to different animals as well so it's a good starting place. I like to do studies of Michael Hampton's anatomy drawings, he separates muscle groups by color, which I think is helpful. Andrew Loomis also put out some very good books which are useful for learning anatomy. Another good way to practice is to download an anatomy app, preferably one with a 3d model so you can rotate and isolate muscles and you can practice drawing anatomy from different angles. An artist who I feel put out some really good videos on anatomy are Sycra, you can find a lot of his older anatomy videos on YouTube, and I always thought they were super helpful because he usually goes pretty in depth. After doing that, it's helpful to do figure studies, and gesture drawing- a good YouTube channel for that is CroquisCafe. They have hundreds of videos of all sorts of different models in different poses. I use it for practicing poses regularly.
I wouldn't worry about style too much just yet, because if you're not really confident with fundamentals like anatomy, gesture, perspective, composition, proportion, etc... style won't help you produce better art.
As far as artists block, when I feel like I can't draw, I usually resort to doing studies of the fundamentals, that usually helps. Also if you draw too much, it can also help to take a break, which can sometimes help the feeling of artists block. The last thing I'd recommend for when you really feel like you can't draw, is just to draw something that's in your comfort zone, and focus on having fun with it, don't care about the results. The more you're enjoying drawing, the more likely you'll produce good work.
Hope you found this helpful,