How can u meditate regularly at the same moment in a day/night

You can set a time when you won't be bothered; early morning or late night right when you go to bed. Making sure that you meditate every day as a hobby can be difficult if you have time restraints or no quiet places, but as long as you pick a time when you won't be bothered in an area that you're alone you will be good. Maybe if you have an alarm set it for earlier in the morning so you have enough time.

Well what I do is I have a schedule set up a morning routine and try to use it for the better. As I do I gout outside write eat my breakfast and meditate and the night just before I sleep
If you want it at the same time use a alarm and make sure your phone or whatever device is charged

Its difficult but its necessary and that necessity pushes me to do it. Your timings can vary though. I like to finish it at a particular choice to make sure my routine stays in place.