Welcome! I'm going to let the more experienced members here help you because I'm a newcomer too, and only have experience with what I'm doing. For what it's worth, I set a daily calorie goal and began regularly exercising just two weeks ago, and I'm feeling better than I can remember feeling in 20 years.
It might be helpful for those who might give you advice to know a bit more about you, like you age, weight, and whether you have any health or lifestyle issues that might affect how you can change your diet or your activities.
I'd spend some time looking around the site, and reading through the forum. You'll learn a lot that way.
Good luck, and keep reaching out for support when you need it. I'm sure you'll get it here.