To set a default assignee for all new requests, head to Organisation settings → Practice settings and find the Auto-assign section. Under "Auto-assign all new requests to user", select the relevant clinician (or team, if available), then click Save changes.
If you'd like more granular control, click Set auto-assignment rules on the same page. From here you can set rules based on request type (Medical or Admin), subtype, or topic. Once you're happy with your rules, click Save Setting, then Save changes on the main settings page.
If you're assigning to a team, you can also configure how requests are distributed within that team — either routing everything to the team as a whole, or automatically assigning to the team member with the most capacity at the time.