Setting a username on your Facebook profile is important, but sometimes new accounts are restricted from creating one. Don’t worry—there’s a simple workaround!
Facebook allows users to create up to four additional internal profiles within a single account. For more details, check out Facebook’s official guide: Facebook Help: Create Additional Profiles.
If your main profile doesn’t allow a username, you can create an additional internal profile. Many users have successfully used this method to add a username, effectively bypassing the restriction.
An added benefit of creating an extra profile is that it gives you a fresh start, letting you build a targeted friends list from scratch.