After getting invitation letter from a friend in china do we apply for Chinese F visa?

Ali, I’m afraid you cannot apply for the F type if the invitation letter is not issued by a duly authorized unit. I’m afraid you can only try to apply for a group tourist L type by booking a tour from a travel agency if you go to PRC for tourism purpose.
You don’t need to make an appointment even though it’s the first time you apply for it.
The required documents include a notification letter from Chinese tourism bureau, the application form, your passport and its copy, and an introduction letter from the travel agency. Your friend may need to provide a guarantee letter for you.
Also, you cannot use the invitation letter to apply for HK and Macau visa. Based on what I know, the invitation letter is not necessary when you apply for HK and Macau visa.