Can’t get motivated

I don’t know why I can’t get motivated. I know I should lose weight and get healthier before trying for baby number 2, but I’m going to be 36 next month and I don’t want to wait. My husband said we can try at the end of this year, but he wants us to both get healthier. I’ve been trying to eat healthier but I can’t seem to control my portions. I’m about 215, and I’m vitamin b12 deficient, and my hands are always going numb, so I’m trying to get my vitamin level up. I was 203 when I got pregnant the first time, but I had a hard time moving with that pregnancy.. and now I have a 3 year old I’ll have to take care of while pregnant. Any tips on how I can get motivated to eat less and start exercising? I don’t want to join a gym. I hate gyms. I’d rather find a way to exercise with my son. I usually enjoy going for walks, but it’s cold and yucky outside!