Literally it means 'not I'.
You can say "Je n'ai pas" in French to mean "I don't have."
"Je ne comprends pas" means "I do not understand" in English.
non je ne sais pas = no, I don't know
I do not have
Je ne sais pas means 'I don't know'.
"je n'ai pas d'animal" means "I have no pet / no animal" in French.
Je ne parle pas français (?) - I don't speak French
"je ne veux pas mourir" means "I do not want to die".
"Non, je ne suis pas," means "No, I am not." in English.
In French, you would say "Je ne comprends pas" to mean "I do not understand."
remarks on "je ne pas de sour": there is no verb in that sentence, and sour is not a French word. I gather that you mean "je n'ai pas de sous" which means familiarly "I have no money"
You can say "Je ne pense pas" in French to mean "I don't think so."