If someone this teaching you wrong thing in your point of view. YOU have the right to correct them instead of they teaching you not getting angry because they tried teaching you. Well everyone is different so they exercise method will be too. SO just relax and go lift till muscles get sore!!!.

PS> getting big on roids is not actually that easy. it takes discipline and patience as well. Dont judge ppl too quickly sometimes they just want to help. But yes please wear a belt when your doing squads or deadlift because you will find out your self after 20 years from now. Your still young thats why your overreacting. Going to Underground gym(aka shoplot gyms is always like that) .