“As” is used properly followed by a subject, then a verb. “Like is properly preceded by a verb and then followed by a noun/pronoun.
Both are used to make comparisons.
“As I have said many times, I do not want you playing hookey like your brother.”
“You will end up a hoodlum like him.”
“If you follow in her footsteps, you will go as she did.”
The use of “like” where “as” should be is an informalism common in American English:
“Nobody does it like you do.”