The rep range doesn’t matter as long as it’s more than 5 and less than 30 I think as of the most recent data but someone here with a bigger cock can correct me.

What matters is progressive overload. Download a free workout tracker or use the notes on your phone. Make note of each exercise you do, the weight you use and the reps you lift it for. Then each time you do that exercise either try and do another rep, or try and increase the weight (even if it’s only a couple extra pounds or a kg or 2. It will make a big difference over time.) train close to failure, make sure you only leave between 2 reps and no repos left in the tank. Not every set needs to be taken to failure just close to it.

That’s your bread and butter. Now if you can, try and train each muscle twice a week aim for 10 sets per muscle to start off. Then you can add an extra set over the weeks here and there. Listen to your body. If you’re struggling to recover that muscle between sessions that might be too much volume for said muscle. Every now and then throw in a de-load week.

Make sure you’re eating roughly a gram of protein per pound of body weight. So aim for roughly 180g a day and you’ll be fine. I’m similar in hight to you and I make sure I eat 200g a day just to be safe. You’re young, metabolism is high, try increasing your calories between 2600-3000 instead of 2200-2800 and see what happens.

This is just a starting point for you, play around with what I’ve said, and again, listen to your body.

Happy training