It's hard to say if you hated the first game so much because the gameplay is definitely based around the original game, but it's much smoother and more fluid, you're given a lot more tools to use, there are a lot more varied gameplay mechanics, and a lot more varied enemy types and environments and level design and stuff (it's not all just forest, forest, and more forest). It feels way less clunky and awkward and like you're constantly struggling against the character and the gameplay, and a lot more intuitive and engaging in comparison.

The story itself takes a lot of style and plot beats from Control and references Control a lot. Personally I liked the first Alan Wake game, largely for its atmosphere, but I can definitely see it's flaws and why some people wouldn't like it, but I felt the second game improved on every aspect by a lot and gave me a lot more Control vibes than the first one did. I actually started replaying Control right after finishing Alan Wake 2 because it gave me so much Nostalgia for Control lol, though at the same time it doesn't feel like it's just copying or just rehashing Control either. The gameplay itself is not like Control though, not even remotely, which makes sense because they're very different games and as much as I LOVE the Control gameplay it wouldn't have made sense to use it for Alan Wake 2. It's definitely based on the original Alan Wake style gameplay on a basic level, but done much much better in my opinion. Some people have compared it a bit to games like The Last of Us 1 and 2 which seems like a reasonable comparison from what I remember of those games. I personally also liked the story and characters and felt that was pretty well done as well, certainly better than the first game imo.

That's the best I can offer you in terms of info and opinion on the game, so it's up to you whether you think it's worth trying out.

Steam no longer sells it separately, they only sell the ultimate edition with both dlc included.

If you got Control via the Humble Bundle, you'll have to buy the dlc through them, and then activate via Steam.

If you have it purchased, it becomes available like 70% of the way through the story automatically. You'll get a quest to interact with the elevator to go to a new map section.