Veterinary Doctor getting professional receipt

Sir,
Namste to All,
I want to know, If a Veterinary Doctor getting monthly professional receipts against his services to a Company (like a full time employee but not a salaried) and total receipts during the year comes above 20.00 lacs than, what he will be liable to get registered under GST or Doctor's Services are under nil or 0%. Or Company as a recipient of services will be liable to pay GST under RCM.