My UE5.1 doesn't fully load projects I saved and downloaded from other sites

For some reason, my UE5.1 doesn’t fully load projects. For example I had a few blueprints and models. But when I load the saved project, it doesn’t show the changes i made, only the starterpack that i started the project with. I still have autosaves and they dont load either.
I’m following a course on gamedev.tv and they provide project files too, i downloaded multiple of those but they all just keep on loading a starterpack and don’t show the other stuff provided in the course.

What do I need to do to get the saved stuff?