SO. MUCH. BROSCIENCE.
Literally don't even know where to start in correcting all the advice you've been given.
First of all, avoid resistance machines. It's a fixed, unnatural movement pattern 'designed' for the 'average' person. Free weights are your friend.
Go heavy or go home, if you're lifting weights, lift heavy. High rep sets (12-15) are not for 'tone', it's for muscular endurance. Moderate rep sets (6-12) promote the most muscle growth. And low rep sets (1-5) with high weights, build strength. There is some crossover between these, so doing ~5 rep sets will build strength and some muscle. If you want to improve your endurance do cardio (running/swimming/cycling or circuit training).
Start squatting now, Squats are a God-Tier exercise for a number of reasons: 1. The sheer volume of muscles it engages. 2. The hormonal and metabolic effect that activating all these muscles will have on muscle growth and fat loss. 3. Psychologically speaking, there's no better feeling than having a loaded barbell across your back, squatting down, then putting everything you have into lifting that fucker up.
You need to be doing compound (uses multiple muscle group) exercises:
1. Squats
2. Bench Press
3. Deadlift
4. Rows
5. Pullups
6. Overhead Press
Get a trainer to teach you proper form, then report back with how he taught you, so I can correct it.
Diet: Go Paleo, if it moves or grows in nature, eat it: fruits, nuts, seeds, meats. Avoid processed/manmade foods, including grains if possible.
I could talk about this for ages...