EXERCISE(S)

✅

Actually what I meant was: (1) to do some exercise; (2) morning exercises

I had a look here - https://forum.wordreference.com/threads/do-exercise-or-exercises.1268024/ . They may be wrong, but they say that "exercise" means one specific excersise, while зарядка means set of different short excercises. And, generally, it's not necessarily in the morning.

To be honest, we use do exercises when we refer to different kinds of exercises. However, in the sense of a daily routine (morning or otherwise), it’s more common to use the verb EXERCISE or WORKOUT.

“I work out every afternoon. On Monday, I do leg exercises, on Tuesday I do aerobic exercises,...”

OK, deleted.
Однако, зарядка - это обычно что-то короткое, что глаголы excercise и work out передают плохо.
Не лучше ли будет что-нибудь вроде I have a (short) workout?

I do a short workout, I do a quick warmup, I warm up with a few (short) exercises, I do a few reps of my warmup exercises... there are lots of ways to say this.

👍