If you consume more than you eat, you'll lose weight.
If you consume less than you eat, you'll gain weight.
To stay nice and dry and pack on muscle, you'll need about 2 grams per pound of body weight. You COULD do less protein but you won't see the gains you could have otherwise. Even if you stay anabolic by keeping carbs (and hence insulin) up, you'll do MUCH better at higher protein levels. Drink plenty of water.
Download the USDA SR19 food calculator. Track everything you put into your mouth. If you're eating less than 3000, eat more.
Contest diet, I'll put 350 to 550 grams of protein, per day through my mouth, and eat 11, or even 12 times a day. I track everything that goes in, from a piece of gum, to chicken to rice, to whatever. Everything gets tracked. Contest diet, I'll bring between 100 to 400 grams in carbs every day, and I'll bring total calories from around 2800 on up to about 4500.
Non-contest diet, I'll put 300 to 400 grams of protein, through my mouth, and I'll eat upwards of 8000 calories some days. Some days, I eat until it hurts, and, then eat extra. I try watch the sugar but about one a week, I eat whatever. I try to stay away from fried foods, 100% of the time. "Off season" I may push as much as 2000 grams of carbs, per day (that's 8000, just in carbs). Normally, though, I'll hit around 800 to 1000 in carbs, per day, "off season".
Folks are skinny if they don't eat. Period. The whole thing is science, but, in most cases, not a complicated science.
How you look is probably more a function of how you eat than any exercise.
If the person advising you is really skinny, non-competitive, or very young, chances are that they just don't have the knowledge, nor the experience, to advise you in a qualified way.
What works for one person may not for another.
Packing it on, though, is about calorie surplus, with no exceptions.
Educate yourself. Study it. Experiment. Some folks do better with less workout. Some need more.
Most young men way, way, way, undereat. Especially gay ones who have deep esteem issues many times. You have to eat.
You won't make gains on a bowl of oatmeal and an apple in the morning, and little else. It will NOT happen.
I stuff food in all day, every day, for years.
I grew up on a ranch in Nebraska. I weighed a lean 175# at 12% when I was 17. That's calories, genes, and plenty of meat, potatoes, ham, and eggs. I haven't been so thin as many of these guys since my early teens, or before. And I had no clue about anabolics when I was 17. Had I been on anabolics at that age, I likely would have packed a lean 200#. Of course, in my early 20's, anabolics, were over the counter, within requiring a prescription, much less all the present day hoopla of misinformation.
You have to fuel the furnace.
I'd bet a Diet Dr Pepper that you're metabolism isn't as fast as you think, but, that you eat for shit.
Do this, if you're serious: get the SR19 calculator. Get a food scale or a postal scale. Track everything that goes into your mouth. Post your findings weekly. We'll see if your metabolism is fast, or if you're just not eating.
Once you start making something more than a minimal effort towards you'll goal, I think you'll find you probably aren't eating nearly enough. Tracking everything that goes into your mouth will be a good start.
Don't sweat your training routine so much. Honestly, it's ancillary to your goals. If you have to choose between working out and eating, you need to be choosing eating.
Core lifts / compound movements are your best choices. You can google about those elsewhere, or pay me to consult you.
Interval training, a few times a week, will be vastly more effective than mindless hours of cardio for a wide number of reasons. It'll help with metabolic activation, take less time, be less boring, and allow you to perform better in your resistance training.
For and foremost, though, if your goal is gaining, set aside all other crap, develop a plan and execute.
1. Get the SR19 database.
2. Track what you eat.
4. Do interval training.
5. Have one day every week where you stuff yourself. Eat until it hurts, then, eat extra.
6. If you aren't gaining a pound a week, eat more.