If formal training is the thing preventing you from feeling you are able to act, put those feelings aside. There is no use in people not acting just because they haven’t spent three years training at an institution. The art form would perish under the weight of it’s own elitism if this were the case. There is a tremendous amount to be learned from experiencing acting in any setting. Getting on set as an extra or a small role will teach you an immense amount about what goes into making a film and the role an actor must play.