Weight lifting calories burned

Now THAT is an easy one to answer... If you're new to weight training.

You should be lifting MORE every session during linear newbie gains. If you run into an issue where you can't recover, you can't lift more weight, (despite deload cycle) increase rest. Increase calorie intake.

You will gain fat and muscle. You will gain more fat than muscle, in fact. It just comes with the territory.

You can probably get really far on neuromuscular adaptations. My wife got to nearly a 200lb squat in calorie deficit.

Me, I couldn't break the 200lb squat until I went into a calorie surplus. So, ymmv.

I have a question here then. If I can't measure accurately how many calories I burn, how can I be sure I am eating enough to build those muscles I am using weight training?

For a person who is comfortably maintaining weight at 1520 cal a day, how much more should I eat assuming I am weight training for an hour 2-3 times a week. Is an extra hundred a day enough. Is there a way for me to calculate that? I'd hate to eat more calories than I should and gain fat instead of muscle.

it's a very customized situation, you can go about it a number of ways, you can be at maintenance or below and max out your existing muscle fiber utilization then add a small surplus to advance muscle growth, or you can start with a surplus and continue from there, both have advantages, but in the end they'll both get you to the same place, you either end up trying to lose more fat at the end, or at the beginning of a weight training cycle. The amount of surplus is really something you have to test and really decide on your own, depending on your body, your routine, your lifestyle, your sex, your age, your starting weight...etc. you can go small like a 100 calorie surplus, and gain lean mass slowly, or you can go fast and add a 300 to 400 calorie surplus, and you might get up to 2 plus pounds of lean mass per 6 weeks or so, but in the second scenario you'll probably add an equivalent amount of fat mass or maybe more. In the first scenario, if you control yourself well, you'll probably add at least some fat mass for that same cycle, it's hard to predict it since there are so many factors.