[Reincarnate]

"Lightly active" usually corresponds to people who spend a lot of their day on their feet, like a teacher or retail worker. It's basically doing the bare minimum to avoid being sedentary.

"Moderate" might be something where you're not only on your feet a lot, but you're also doing a lot of moving (like a waiter, etc).

If you've got a demanding job and you also do a little tennis, my guess would be "Moderate" and I'd start somewhere around there.

But really, you can also count your calories for a while and see how your weight changes in turn, and get a better sense for what your real TDEE is.