You may be confusing git with GitHub.

git is a version control tool that lets you keep and manage a history of the files you are editing

GitHub is a website (not directly affiliated with the group maintaining git) that lets you upload, backup, and share your code using the format used by the git tool.

source control just refers to software to manage your source code in some form. git is the most popular tool of its kind, but there are others, for example mercurial.

Since OP’s project wasn’t tracked, it got detonated.

This is the biggest part of the problem. Using git directly, it just ignores files that aren’t tracked.

You’ll feel right at home in the command line. Install Homebrew or MacPorts. These are command line package managers. Many if not most of the software tools you are used to on Linux likely have Mac versions as well and you can find them either online or via one of those package managers.

If you are going to download software from Apple’s Apple Store, you will need to make an account. You can install software directly from the internet without needing an account. You might need to tweak some “security settings” in System Preferences to run software not from the App Store.

Unfortunately Xcode is something you need an Apple account to install. However, the Xcode “command line tools”, which includes a lot of common tools like gcc, I believe you can install by running “xcode-select --install” from the command line even without an account. There might also be other ways to get those tools installed manually / not through Apple

If you just want an IDE and really want to avoid making an account, just use VSCode or something. But if you will need to develop Mac apps using Apple’s APIs, it will likely be easier at the very least to work in Xcode. And if you are going to develop for any of Apple’s other operating systems (like iOS) you will need to make an account.

Or the Supreme Court makes something up about why it doesn’t count