Hi! I have a lot of questions so im going to sum it up in the end, might be a bit messy to read this post, bear with me.

My name is Even, im 18 years old from Norway and i've never been a guy to work out at all really. however, since im joining the army in like 6-8 weeks, i figured i would work my ass off until the army so i can be in somewhat of a good shape! So thats why i bought myself a boxing/punching bag of 40 pounds / 20kg. My knuckles hurt alot after and during the punching work out. mainly my right hand (the little finger and up to my middle finger) hurts the most. it's really numb and has swollen up quite a bit.

Pushups: I've started a pushup excersise which should take 6 weeks to complete. (Its called 100pushups)
Jogging: Trying to jog between 2-4 times pr week, can only jog for about 15-25 minutes nonstop before im tired and have to take a break.

Regarding food and such, do you have any tips as to how my routines should be? Im trying to eat alot of eggs (atleast for breakfast), fruits every now and then and pretty much trying to eat 6 times pr day instead of my normal 2-3. Drinking alot more water then i've usually done.

If wanted, i could post pictures of stomach so you could see my progress (if i can keep the work out up for the next weeks.)

So here are the questions:
1. How can i stop my knuckles from getting hurt so much when boxing?
2. How can i increase my stamina when boxing? (can only box well for around 10-15 minutes before im all out, and im a tiny man so i cant hit very hard)
3. Tips and hints as to what i should eat/drink for the different excersises ?
4. tips and hints as to how i can improve my quickness/ability to jog further/more?

Anything that does not have anything to do with these questions, but could help with my training is much appreciated!
Thank you in advance.