If you are new to working with SFDX and Git, the easiest way to get started is by cloning the Hutte template repository. If you work with GitHub, you can create a copy of it in your own GitHub organization directly from this link.
Alternatively, you can create an empty Git repository on your local machine. Then, create an empty Salesforce project, using the sf project generate --name <ProjectName> command. In a next step, add the created files and directories to Git (commit them) and push them to a remote repository which you have created on any of the Git hosting providers supported by Hutte.
You are done! After connecting Hutte with your Git repository containing your Salesforce project, you can start tracking Metadata there easily.