Never had an argument in my life as a kid ..so now as an adult when someone fights with me i have no comebacks and pretty much stay silent

So like the title, pretty much says, let me start with the very beginning. My father is in the military so we had many transfers in my childhood. Every time I transferred to a new school I got to meet new people. I made friends with them and for some reason all of them were pretty nice. No one had ever argued with me, and so my priming for arguing with people was never done in my childhood. Also, I never met anyone who was in general, rude or straight up pathetic in my school life

Fast forward to my college life. Now that I have moved to a new state and am an adult I find it very difficult When I see how harsh some people can be. They never think of the consequence their words can have on other people. One of my major reasons to stay silent in an argument is that I don’t want to unknowingly in anger speak something that might stay with the other person forever
But it seems pretty sad for me that I look around people, and they don’t have this sense of sensibility in them

But also at the same time, I find it pretty sad for my own self dignity that whenever someone fights with me, I stay pretty much silent because I have never argued with anyone, so I don’t have any experience of fighting or having comebacks in my mind while fighting with anyone