To add a new user, simply open the Revolut Business app, go to Home » Team » Add member. You can choose their role within the account and manage their permissions when creating their profile. You'll also be able to manage those permissions in the future by going to the same menu and selecting the profile you’d like to edit.
Please keep in mind that you can only invite team members who are residents from eligible countries to be a part of your Revolut Business account. Without a proven physical presence in EEA/Switzerland (local ID document or residence permit valid for at least 3 months) such team members would not be able to pass their identity verification process.