How to create a Service Plan in Plesk?

1. Log into Plesk
2. Switch to Service Provider view
3. Navigate to Service Plans and select Hosting Plans or Reseller Plans
4. Click Add a Plan
5. Perform necessary adjustments in the tabs (Resources, Permissions, Hosting Parameters, etc.)
6. Click OK to save the Plan

Execute the following API request:

# curl -X POST -u admin:"<password>" "https://213.0.1.2:8443/api/v2/cli/domain_template/call" -H "accept: application/json" -H "Content-Type: application/json" -d "{ "params": [ "--create", "Test"]}"

Note: The utility domain_template is the same with service_plan.

Check documentation