Now after being the reasonable voice:
Your response (both of you or whoever that is) to getting hit is to turn your head and back up that's the natural response for most guys against punches coming in but it's the wrong one (at leats in the way you guys do it).
You can fight with your hands down but you should always be able to put the earmuffs on just in case it doesn't work if you can do that and fall back to that if your thing doesn't work and you still feel more comfortable fighting with low hands then you can do it.
That for the defensive side well you should also move your head but you won't be able to do that if you tried without knowing how so atg the moment just put your hands up.
Also you can back away but it'sthe most crucial mistake and the most common:
Don't cross your feet. If you move backwards your back leg moves first and if you move forward your front leg moves first and it will feel unnatural in the beginning but you have to force yourself to do it.
it of course means that if you move to the left your left leg moves first and to the right your right one. The leg in whichever direction you move moves first.
Also neither of you knows how to throw a punch. And you should also move your head as I've said but that's too long to explain and you would probably not get it (no offence) if I just wrote it.
There are YT vids on how to move your head, how to move and how to throw each basic punch (jab, straight, left and right hook and left and right uppercut) so you might as well watch them.
And before all of that you need to get your stance right as simple as it may sound you must stand properly that's the first thing to do. There are also videos on YT on how to for pretty much all basic stuff there are youtube videos and it's probably easier to watch it yourself than if I explained it here.
But if you really like striking and want to learn everything much easier, better and faster then go to a boxing, MMA, kickboxing or Muay Thai gym.