1. You can go home now.

2. You are able to go home now.
3. You are allowed to go home now.
(I allow you to go home now.)
4. It is possible for you to go home now.
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It is a little confusing. If somebody says, "You can go home now," what does that mean? Does #1 mean, #2, #3, or #4?

Sentences 2, 3, and 4 are saying that your home (or maybe you) is in no danger anymore and it's okay for you to go home.

Sentence 1 can mean the same thing, or it can be a dismissive statement implying "we don't need you anymore."