There isn't really a "should" when it comes to fitness.
You "should" do as much as you are safe and comfortable to maintain for a lifetime habit. Then, given how much exercise you actually do, your food recommendations can be expressed as suggestions.
No system can recommend two variables when they each depend on the other. You have to know one of them first to get anywhere.
For best results, generally speaking, get some strength training 2-3 times a week and cardio 3-4 times a week. For both, quality is more important than quantity.
Deb, in New Zealand