Does can age really stop or slow down theoretically or realistically? Is time affected by aging?

Your question is too vague. Also, it is in a wrong forum, so it is not even clear if you're talking about time in physics, time in psychology, or something else.

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Moderator Note

Moved to Physics, although "aging" has more biological aspects, but let's establish what the question means wrt time.

 

Time is relative to the frame of reference of the observer, being affected by speed and position in a gravitational field.

Aging is a more nebulous concept. As Phi notes, it’s probably a biology issue, so you should specify which concept you wish to discuss.

Aging does not affect time. Time affects aging.

Aging (old|new; eld|young) is resultant from organic factors: ghenetic, cellular, and biochemical; that is, cellular senescense, DNA damage, oxidative stress, telomere shortening. Organisms are subject to time; time is not subject to organisms (or aging).