Yes!
For one-offs if they are with you in person: we ask that the second participant creates a free account to sign the terms of service. You can take the class with one registration, but we do ask that you write in the second person's name in the registration notes, and make sure that the camera is showing all participants. (Kids are also welcome, although we do have kid-specific classes they may also enjoy!)
What about all the time? We do ask that if you have multiple people for regular practice they sign up for their own membership so that we have waivers for everyone and can fairly pay our teachers! (Then you both would register for class but can share a camera!)
If you have someone else in the household who wants to take their own classes they can sign up for the friends and family addition. (If you get Ompractice from an employer or an organization, they may also give access to your family members.)
Invite a friend to join a Community Class. These are free to the community without membership. (All someone needs to do is sign up for a free account.)