You need 'Manage employment' rights for your own or other teams to be able to add freelancers.

If you don't see the button to add freelancers it means you don't have those rights. You can ask the restaurant owner to do it or give you more rights. They can do this in Settings > Managers > your manager profile.

To add freelancers, go to People and click the ⋮ icon in the top right, then click 'Add freelancer'

Currently you can't create freelancers from applicants in Recruitment. You can only create freelancers as described in this article, so from People > more options > Add freelancer. When you have an applicant you want to turn into a freelancer, you need to take their data and add it as data when creating a freelancer.