Some small addition to the last option:
If you want to browse a community from a specific instance on your home instance you have to add the ‘home’ instance.
For example your home instance (where you did register your account) is Lemmy.ml and the community you want to interact with is on Lemmy.world you would use:
Https://Lemmy.ml/c/nostupidquestions@lemmy.world
In order to be able to post, reply etc
Are they really that desperate now?