l do not even know the different types of punches, so allin simplest terms possible please!
Thanks to everyone who is responded, that is really helpful.

Happy New Year!

You should probably just sign up at a local boxing club. But if you do not wanna do that, there is pretty much no use in doing it. Sorry.

thats absolutely not true dude, here is something:
l have a punching bag & here is something that l do:
steps:
1. l worm up, punch a little slow not so hard hitting.
2. Then l start hitting harder, u should focuse & try to dance, & as in dance, l dont mean litterally, boxing-dance :p move around & pretend the bag is ur oponent, watch out of him.
3. Do a simple moving & use ur lefty for 100 punches, it is depending on how much u can handle, if u already have a good base of strength, u should aim for 100-200 punches maybe.
4. Then the same thing with ur right arm,
5. The last one, punch freely, exhaust yourself, punch until u can not punch no more :D or atleast until u feel like u got a hell of a workout of strength or so. Also, the very important thing is to keep on moving, stay on ur toes & keep on movin'.
Even if you're not planing on being a pro boxer xD it is still a good work out.

This exercise can come to 30min, depending on how fast u r & if u can handle the amount of punches.

go on it.

trow 10 jabs
10 crosses
10 left hooks
10 right hooks

uppercuts etc.

after you get does punches rite ..
do your own combos.

after that practice it everyday for 3o min..

You do not worry about what kind of punches now, just punch non stop for 1 minute then rest then punch again then stop. Eventually go up to 2 minute then finally 3 minutes. You will have a great workout.
Happy New Year.