Informal dinner does not have formal dinning ettiquette to follow

English as a Second Language English Vocabulary, Grammar and Idioms
1
  1. We are just having an informal dinner with close friends so there is no need to conduct myself so formally at the dinner.
  2. Informal dinner does not have formal dinning ettiquette to follow.
  3. Informal dinner have informal dinning ettiquette whereas formal dinner have formal dinning etiquette.

Can somebody tell me if the above sentences are correct? Please help.

2
  1. We are just having an informal dinner with close friends so there is no need to conduct myself in a formal manner.
    More naturally:
    We are just having an informal dinner with close friends so I don’t need to act formally.

2)There is no formal dining etiquette to follow for an informal dinner.

  1. An informal dinner does not follow a specific etiquette whereas a formal dinner has a formal dining etiquette.