The Wca stands for World cube association!
If you search up wca on google then it will show you a section called compitions, this is where you sign up for one.(You also have to make a account)
You should always remember/read the regulations before you join a compition
If your in a compition remeber to not get shivery, this might ruin your times.
Also remember to actually stop the timer. That's what I did and got a 1-minute solve.(bad)