How to set up remote to EC2 config file when using a MAC

So I'm trying to deploy angular-fullstack to an ec2 instance.

I found an awesome example video on youtube however, one of this examples for a .git config file has a windows spefic key puttykeyfile which is windows specific, I rather have a pem.

Client Side - Create git repo and add a remote into config file

[remote "AWS_production"]
    url = ssh://ubuntu@YOUR-IP/home/ubuntu/repo_do_not_delete/
    fetch = +refs/heads/*:refs/remotes/repo_do_not_delete/*
    puttykeyfile = C:\\Users\\YOUR-USER\\.ssh\\private.ppk

Question: Using this block of text from windows. How would I change puttykeyfile to reflect my pem inside my /Users/matthew.harwood/.ssh/private.pem folder?