I new to the comunite and I would like to know, if I stop the run and the timer, can I continue in another time. It would still be valid?

This is generally only allowed for very long runs (think 24 hours +). If it is not explicitly mentioned in the category’s rules that it is allowed, then assume it isn’t.

If it is written S + Q means it is allowed?

That probably just means that you’re allowed to quit to the menu during the run, not that you can stop the timer to take a break.