So I've create a new repo on remote, and managed to connect it (I belief) to client (Git Kraken). Now it want a branch name from me for a repo that doesn't have any. Note that its also ...push/pull with "master":, that is master with a colon. Pretty much explaining a mechanic that is at play here is as welcome as actually drawing out steps.
You'd need to "Set Upstream" for your local branch. To do so:
To avoid confusion, you could also name your local branch (to keep it the same as the remote) at the time of creating the branch from master or whichever remote you want to branch from.
Note: Though there shouldn't be drastic differences between versions, the above is based on GitKraken 2.5.0 64-bit (non-pro version)