itch.io

This will suffice. Just fyi, game engines have cache folders that you don't have to upload as part of source. For example, if you were working with a team, you wouldn't send 15GB of project files to another team member. You would remove most of it (since the cache files take up the majority of that space). See this gitignore for files typically excluded from a project when working in a team: https://github.com/github/gitignore/blob/main/UnrealEngine.gitignore