You can use github topics for technologies you are interested in which act like hashtags on other social media sites. If you are looking for curated lists, start here:

https://github.com/topics/awesome-list

If you are looking for a single page option, check this out:

https://project-awesome.org/

I typically discover repos through p2p sharing, looking up a solution to a specific problem, and hanging out in my favourite programming languages' communities on socials. People also share things they have built in hobby communities, blogs and youtube.