gin[1] is a popular off-the-shelf solution that provides a lot of functionality for you. But as everdev said, it's pretty normal to gradually build up your own stack using the stdlib and possibly some smaller, more focused packages like httprouter[2] and the gorilla toolkit[3].

I actually have learned a lot about HTTP/HTTPS servers by working on a lower level and building up my stack! I recommend just starting with the stdlib and importing 3rd party code where you feel yourself limited by it. The first thing people probably adopt is a more expressive router.

[1] https://github.com/gin-gonic/gin

[2] https://github.com/julienschmidt/httprouter

[3] https://github.com/gorilla