Have you tried adding legumes like lentils and beans into your diet? They are also protein sources but are cheaper than meat. Lentils are also great in salads. I also use baked tofu in salads.
I can tell you that whole foods can only you get you so far. Right now, I don't count calories but I do weigh my food so that I am using portion control.
As far as exercise goes, start slow. Even a 10 minute walk/day is better than nothing. Then start increasing. Start incorporating other things like 10 minutes of strength training/day, as I said previously resistance bands are great for that. Even if you say "I'm going to do 20 wall pushups per day", that again is better than nothing.
And something that might help you that is helping me is I'm reading a book called "lean habits for lifelong weight loss". It is a science based book that presents habits that are common in those that are at a healthy weight. Basically, you get 1 habit and 2 weeks. I don't know all the habits because I just started and I'm not reading ahead but the first habit is to eat every 4-6 hours and then explains why it works (with scientific studies). Then the next habit is to feel hunger before eating (30-60 minutes is ideal but she says you can start slow if that is intimidating). The idea before the first one is that many people snack their way into weight gain/maintenance and the second one is just to help you get in touch with your bodies cues.