Once you have added in various appointment types, you'll have the ability of editing the procedure display name, which patients can schedule a procedure (new or returning) and most importantly in this case - assigning a practitioner to specific procedure types.
If you do not know how to integrate appointments into Kasper, access the "Adding Appointment Types" article here!
Simply head over to "Settings" (from the sidebar) and then click "Online Scheduling" from the categories in Settings.
You will see a "Providers" column for each type of procedure, for which you can click on
Now simply select which providers you will allow per procedure