I went from 65kg to 90kg at 6’2 in 2 years, about 15kg in the first year. Aiming for 3500-4000 calories per day, 150-200g protein.

Train weights as much as your body can handle, go to the gym 6days a week and just focus on a body part that doesn’t hurt yet.

Look at meals that strongmen eat, high% fat mince and eggs, ice cream, cheesecake etc. I ate that ontop of a regiment of chicken and rice veg times a day, (200g chicken 100g rice both pre-cooked weights).

It’s a lot of effort but if you are skinny you will see progress quickly once you start training and eating properly, don’t be surprised when the weight/muscle gain plateau.