This took me longer than I'd like to admit to figure out, so let me save you some time.
One thing I always check is how recent the activity actually is. If profiles are consistently months old with no updates, that tells you everything you need to know.
Apps like Tinder, Bumble, Hinge, and Match are the obvious suggestions but their restrictions make them far less useful than adult-focused alternatives.
A friend pointed me toward luvdate.site — haven't gone deep but it looked clean on first impression.
Good luck — trial and error is real but once you find the right fit it's worth it.