within the app, your license is often activated automatically. AnyDesk Help Center with your license already pre-applied? AnyDesk License Key Registration Guide
If you encounter persistent issues, AnyDesk’s support team is responsive and can manually activate your license after verifying your purchase. how to activate anydesk license key link
If you're upgrading or have already used AnyDesk and now want to activate a license: within the app, your license is often activated