Thanks for posting.
First the TDEE is an estimate so this is similar to following a training template. You start out with the estimate and then you deviate based on your response (weight loss or weight ggain depending on the goal). So I would never get too wrapped up about being super precise with that. Just start on a calorie level that makes sense and is less than what you are currently on and scale down from there. To answer your questions
1) You won't until you've tried it for a couple of weeks. Pay attention to hunger cues as well. If you are mildly hungry at the end of the day you are probably in a deficit.
2) I don't think you are at the highest activity level but I do think you are up there given the amount of weight you are lifting and the recovery required for that.
Does this make sense?