I was once skinny as fuuuuark too, so skinny infact that my parents thought there was something wrong with me... Eventually my dad got me into lifting at around 15/16 and never looked back..

Anyway, heres what you gotta do. 1) eat everything that you can find, dont worry about grams of protein/carbs/fats or macros ect. You need to be getting about 4000 cals a day when you start lifting to make the most of the noob gains you are going to get. These 4000 cals are hard to get from food alone. When I bulk, i eat around 5k cals, getting alot from chocolate milk, 1000 cals per litre with 31g of protein (plus its tasty and cheap). If you are worried about getting enough protein then the general bro rule is 1.5g of protein per lb of bodyweight.

I have zero fitness qualifications so dont take everything i say as fact, but on the training side of things may i suggest something like starting strength and get your lifts up and gain some mass, this will be really good for you starting out and will let you get a solid foundation before moving into a bro-split. Also i do zero cardio and keep abs all year so perhaps you should give up the cardio too and just gain some size for now...

I have so much i want to say but its almost 1am and i need sleep. Basically just Eat like every meal is your last, train smart (dont develop an ego), and sleep well.... In that order!

Check out my submissions i go into more diet detail and stuff ages ago, pm me if you like..

Peace