Yes, SELinux is enabled (in “enforcing” mode) by default in Fedora. In my experience, it doesn’t hamper usability.
I remember seeing old advice from blogs and listicles about turning it off, on the theory that it might get in the way. But it’s better to leave it on if you care about security – especially if you want to learn.
When SELinux blocks a piece of software from doing something sketchy, an alert is generated to explain what happened and why. That’s rare but it’s a learning opportunity for you, not to mention preventing a potential security threat.
See rules 5, 6, and 7 in the sidebar.