You may find many templates in the links attached below. These are your point of reference. It would require editing depending on your requirement and the terms that you may have to offer as an employer.
I would be thankful if you can provide me following HR letter for Newly Started IT Company.
Offer Letter for Consultant/Contract
Appointment Letter for Consultant/Contract or any other letter
Contract to hire letter
Designation Change Letter
Resignation Acceptance letter
Kindly do the needfull.
Thanks and Regards,