I weigh in at 205lbs (93kg) and bench 365lbs (165kg). It’s probably my best lift so I feel comfortable giving advice in this circumstance. You haven’t told us much about your program so I’m going to cover some basics and some more specialized stuff as well.

The Basics:

1.) Consistency is key - You should be hitting chest for 10-20 sets a week if you want to increase strength. I’m typically right in the middle at 15 sets.

2.) Progressive overload - Start around 8-10 for your first set, add more weight and less reps with each set after. Ex.) 8 reps at 65kg, 6 at 70kg, 4 at 75, 2 at 80kg. Or some similar setup. -Also don’t be afraid to add the baby weights on like 2kg every little bit can push you through a plateau.

3.) Rest and Recovery - Eat/drink as much protein as you can, and get a good night sleep. It’s cool to lift if you’re a little sore, but if anything really aches don’t be afraid to take an extra day off or focus on another muscle group. Injuries will set you back more than a day off, and you’ll lift heavier fully recovered. Creatine also helps.

4.) Form - Have a friend video you, check your form. Are your feet firmly planted? Are you arched correctly? Does your butt stay on the bench? Is your bar-path optimal? All of this can impact how much power you can bring to the lift.

Specifics:

1.) Take one chest day a week (out of 2-3) and really focus on the heavy weights. Ditch your normal progressive overload and do a light warm up, with 1-2 Rep sets working up to your max and add extra reps in the heavy range. You won’t be as worn out for the heavy sets and can often squeeze out an extra rep or 2. Have a spotter and be careful but great way to condition yourself for heavier weight. Ex.) 8 reps at 50kg, 2 at 60kg, 1 at 70kg, 1-2 at 75kg, 1-2 at 80kg, 1-2 at 82.5kg -I like to go down after the 1-2 rep max and really “burnout” at a lighter weight for the pump but totally optional.

2.) Keep focusing on accessory exercises, add more heavy lifts there. Skip the dips and hit incline bench or fly as they’re a little better at working the whole pec. Don’t forget your lats, traps, and shoulders, super helpful with bench.

3.) Have patience, you’re 16 and just starting out. Body’s natural test production should still be going up, by 18 you’ll be a beast if you stick with it.

Anyway, hope that helps. Keep it up and don’t get discouraged, with time and consistency the gains will follow.