I wanted to know in which format i am supposed to submit the invitation letter during my visa application process

Hi, the invitation letter shall include the following items:
1. Personal information of the invitee: name, gender, date of birth, etc.
2. Information concerning the invitee's visit: purpose of the visit, date of arrival and leaving, places to visit, relationship between the applicant and the inviter, and who will bear the cost of the applicant's accommodations.
3. Information of the inviter: name of the unit, phone number, address, seal and signature of the legal representative.
Generally, the invitation letter may be submitted as a fax, copy or printout. If necessary, the consular officer will ask the applicant to submit the original one.