TN Visa - can I work as a manager and employee or only as contractor?

Was working under OPT missed cap company offered TN Visa I am from Mexico

Also, can company that is not a consulting firm but a CPG comapny employe me over 1 yr or is there a limit for them? could i be working as a brand manager under a consulting type of visa or role?

Not sure How TN Visa works. Please talk to an attorney.