Permission in Specific Repositories using SSH KEY

[lucasnavigatetravel]

Hello Guys!

I have following situation:

I have more than 5 repositories in bitbucket cloud and I would like to give permission based on ssh key in ONLY one of those repositories.

If I add ssh key under repository its does not have permission to push code in branch (apparently this is a deployment key ? )

If I add key under my bitbucket account the key has permission to PUSH code, but in all repositories of my account.

How can I give full permission in specific repositories using ssh keys? 

Also I would like to know how can I limit permission to PUSH in specific branches using ssh key? (I had a look in branch permissions, but when I tried to do that in my bitbucket account its only give me the option to select existent users (not keys).

Thank you so much.