Gaining weight the healthy way

I need help!! So I need to gain my weight and strength back before the summer so I can go back to work but I’m just struggling so bad on what to eat.. I have absolutely no idea what to eat for breakfast, lunch, dinner, or snacks. I used to just eat whatever but now I’m at the lowest weight I’ve been since high school. I tried looking up recipes, getting recipe books but I just can’t bring myself to go through each recipe, buy all the ingredients for each individual recipe, make every meal, it’s exhausting. I believe a lack of motivation is the main culprit but I was just wondering if anyone knows about an app or website that helps with meal prep for gaining weight? Thanks in advance🙂