Looking to gain weight and Muscle for Holiday !

[Grazoink]

Hey im 19 yo nearly 20.
I am slim built , but have tried to gain weight through the correct diets etc , but I have a fast metabolism which is a pain!. I went to the gym for a couple of months but stopped. Tried working out from home.Decided to motivate myself start a new diet and rejoined the gym. I need advice and tips , or personal experience.

My questions

What should I work on at the gym
How should I gain weight
Do you think it is possible to gain some muscle before July 26th.

Here is what I look like right now ( sorry about the mess in background ). Embarrassed of how thin I am but want to bulk up to feel confident.

Here it is :

 

[SXIPro]

You are going to need to eat a lot of good, real food. Lean meats, fish, chicken, eggs, milk. Also plenty of fruits and veggies.

In the gym work on movements that target your large muscle groups. Bench Press, squats, dead lifts, etc. These are more important than isolation movements like curls. Lift as heavy as you can safely and with good form. Stay on the 6-10 rep range. Keep increasing the weights as you progress. There are a lot of good routines out there. Do a bit of searching and reading on here.