How many hours of practice do I need per day?

The question is in the title.

Need for what is the question

There is no formula to "how many hours of practice do I need per day in order to improve", just play and have fun

You'll get better by the time.

It doesnt matter. You dont learn chess overnight, its an ongoing process.
As long as you keep learning, you can do it at any pace you want. Obviously, you are going to see faster improvement if you study a couple of hours a day than if you only study half an hour.

I once went to the serious phase of want to improve asap. I was investing about 4 hours a day x 7 for about 5-6 months.

Chess is my favorite activity, but the hell ill do that again. 2 hours at most.

You can just play a few minutes at day and you will eventually get better

practice what you consider sufficient, or as long as fits your schedule

To learn mathematics deeply enough to be a researcher, I tell my students that 2 hours/day is too little and 4 hours/ day is enough but it must be your best 4 hours [when your mind is sharpest] and without distractions [cell phone off etc]. It takes the first 2 hours to bring your brain to the frontier separating what you understand from what you dont enough times to force it to bear down there. Then the next 2 hours pushes it out further. Beyond 4 hours it's hard to go further mentally. Time beyond 4 hours yo can spend having fun of writing or other things but sustained, deep mental effort needs time away to process new information.... my guess would be similar for chess. 4 hours of deep, undistracted, focused mental effort sustained over months and the rest having fun with chess. Chess players generally develop strong powers of concentration so short term I'm sure more is possible.

#1
There is no specific time for practice. Practice chess as much as you can in a day but don't exhaust yourself.
Play on a regular basis and do puzzles.

studying some master games and concepts followed by 100 simple tactics followed by 5 games should be a good start