30 min or 15/10. Generally, beginners should strive for longer time controls. The amount of time you should spend on a move depends on the position, but usually around 5 minutes is good
Time Control

Depends on the person; not necessarily the play chess ability, but the actual person themselves. Some people naturally move faster (for better or worse). Especially as a chess beginner (but even as a more advanced player), you should be playing a time control you are comfortable with and not feeling too rushed in. If 5 minutes per game feels sort of comfortable for you, then you should probably be playing 10 minute games to give yourself a little "extra" time if you need it. If 30 min games is more comfortable for you, then maybe 45 min or 1 hours games is what you should be playing.
What you do not want is to feel rushed. The best bullet and blitz players in the chess world are also the best chess players at long time controls - this is no coincidence. You can naturally get faster once you learn more opening theory, learn safer premoves (only for online play) and maybe even learn opening systems/structures.
How long to spend per game? Answer: depends on the person.
How much is usually needed? I'd say at least 10 min. games with emphasis on "at least" - maybe 20 min or 30 min is better and many experts recommend even 1 hour games if you have the time.
Just remember that for time controls, you must double the time since their are two clocks (one for each player). With no delay or increment, a 20 minute chess game could actually last up to 40 minutes (20 minutes per player). I wouldn't recommend anything shorter than 10 minute games to start with (so 20 minutes total since it is a maximum of 10 min per side) and maybe 30 min games (up to 1 hour for the entire game) is better if your schedule can allow for it.
@brisket it depends what you want out of a game. If you are playing for fun, then play whatever time you enjoy. If you are playing to improve, then the longer the better as you will have more time to think and develop new skills and habits. Short games tend to exercise existing skills and knowledge, play is more reactive, long games help you develop new skills and knowledge because play is more contemplative. Both are fine but you are less likely to improve quickly playing short games. All depends what you want. IMO G30 or longer is a good control for improvement.

What is the best time control for a beginner and on that time control how much time should be spent on each move? I obviously understand the first couple of moves might be quicker than ones that require more thought.
start with rapid, then try 10 mins, then 5 and just find the most comfortable time control (despite me being a complete beginner Im best at 10 or 3+2)

It depends what your goals are. If you wish to improve your game, longer time controls are better. 1 hour especially, and even 30 minutes per side are excellent because you really get to think about the position on the board.
If your goal is just to casually play and spend some time, you can choose any time control.
Now, if you wish to improve, and are willing to do a bit of reading, check this out:
https://www.chess.com/blog/nklristic/the-beginners-tale-first-steps-to-chess-improvement
It is a guide of sorts that answer your question and offers you a slow but steady way to improve your game.
What is the best time control for a beginner and on that time control how much time should be spent on each move? I obviously understand the first couple of moves might be quicker than ones that require more thought.