One of the things I used to have to look up all the time were grilling times and temperatures. Over time, I've figured out my own rhythm with my own grill, and I know a lot of these by heart, but I know for grillers just starting out, sometimes time and temperature are the best way to get started. As far as if your meats are done, you should definitely invest in an instant read thermometer and make sure you've cooked it to a food-safe temperature, but these guidelines will give you a sense of how long to keep that meat on the flame. For steaks, you have to also consider the thickness of the steak, so there's a little more nuance to it. But you should preheat your grill to 450° and let the steaks sit out of the fridge for a while to reduce some of the chill. My grill has a searing burner that gets nice and hot to make the grill lines, then I can finish on the other side of the grill with a slightly less direct heat source.