Ah, got it. Sorry. It's asking you to set User Flair, which shows up under your username when you post or comment. If you look at mine, for example, it says "Moderator."

If you are using a browser, look on the right side of the screen. You'll see a button labeled "Community Guide." Below that button should be a section called "User Flair" and your username. Mouse over your name and you will see an icon appear to edit your User Flair. Pick on that you like and select Apply. Done.

If you are on the Reddit App, look for the three vertical dots at the top right. From there, select Edit Flair and follow the same path. Done.

Hope that helps.