How do you become eligible in Fortnite?

I'm curious about the eligibility requirements for Fortnite. Could you please explain the process in detail? Do I need to meet certain criteria or complete specific tasks to become eligible to play the game? I'm particularly interested in understanding the age restrictions and any other potential barriers to entry. Additionally, are there any costs associated with becoming eligible, or is it a free-to-play game? I'd appreciate any insights you can provide on this topic.