Which sentence is grammatically correct?

1) It isn't work that way. You must follow the instructions carefully.
or
2) It doesn't work that way. You must follow the instructions carefully.
”

Only the second one is correct. Use [does / doesn't] before a verb without -ing. Use [is / isn't] before a verb with -ing and before nouns, adjectives, and prepositional phrases. (An adverb may intervene.)

It doesn't work that way. He doesn't really know how to do that. She doesn't usually study in the morning.

It isn't always working right. He isn't going with us. She is planning to eat later.

He is a carpenter. She isn't a nurse. He isn't happy. She is often in the garden.