How to hide post content/meta from everyone except the post author and admin

I’m trying to start myself off here but I can’t get my head around it…
How can I hide an author’s post content/meta from everyone except the post author and admin? This is my scenario…
Schools and teachers publish their own custom posts
Schools/Admin can see all teachers posts but only the teacher who published the post can see their post, other teachers can’t see other teacher’s posts.

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