Weight gain is my goal

Hello everyone, I have been trying to put on weight for a while but never really got very far, I recently started going to the gym to improve my overall health and fitness (which is currently pretty bad) and in theory put on a little muscle as well.

I joined my fitness pal to help me figure out how much I need to be eating etc in order to gain a little weight and more importantly not lose any at the gym.

I know a lot of people are here to help with weight loss so it would be great to hear from any people who are looking for gain.