If you used lean ground beef, you shouldn’t need to drain it. However, if you used anything under 90%, you’ll likely have rendered fat in the pan, which you’ll want to discard. Ground turkey or chicken can be used instead of ground beef if preferred.
You can use soft corn tortillas instead of flour tortillas. I've noticed that corn tortillas tend to get crispier in the oven if that's your fancy, though they aren't as sturdy as flour tortillas.
I'm partial to homemade taco seasoning, as you can control the intensity and flavors that go into it. However, prepackaged taco seasoning works just as well!