The only way to get a new username is to create a new Reddit account. And select the username you prefer. Unfortunately, Reddit does not allow users to change or modify usernames in this manner, so you have to create a new account. Create a new account if you want to change your Reddit username. On many websites, such as Instagram, YouTube, and Twitter, you can change your username at any time. The username on Reddit can be changed easily, but the display name must be reset.
Change Your Reddit Username
The first time you log in, a prompt asks if you want to change or keep your username. Reddit asks you to confirm that you want to keep your Username and to change it. Click Save as username to finish the process and go back to the location where you want to store your username.