Question

I want to join two different git repositories into one repository with two branches. Is it possible? How?

Answer 1

Create a new repository, then add both of these repositories as remotes:

git remote add origin1 ...
git remote add origin2 ...

Fetch from both:

git fetch origin1
git fetch origin2

Create a local branch to track a branch of each remote (assuming the master):

git branch branch1 origin1/master
git branch branch2 origin2/master