1) What habit you might have developed from playing games? Both good and bad.
I tend to always look for ways to optimtize things, in games if I notice dashing or triangle jumping makes me move a bit faster I do that even if it is excessive... I take that into real life too which can be great for work, but not so great for like... Cooking... Which I often screw up because I tried to make it faster.
I also do things like studying statistical probability in board games and apply that to my gameplans to help deal with uncertainty.
I have also developed excelent spatial memory thanks to videogames... Like i can vividly remember a hotel room I went to over 10 years ago on a trip to the beach, even though I can't remember the people that were there with me... I could actually draw you a map of the places I was too even today xD
Probably my worst trait is my competitveness... When I play a game, ANY GAME, my default brain is to try 100% to win... I often have to remind minself to tone it down when playing for fun otherwise I get super anxious and irritable, especially when playing with friends.
And last but not least, I move around a lot while thinking... I only noticed this recently, but sometimes when I'm like playing a game and there is a puzzle I'll often jump around or do anything I can as I try and figure it out... I noticed I do that a lot in real life too, when i'm not busy i move through every seat in the house trying to find something to entertain with.
2) Any gaming jargons you use in everyday life?
I actually have always tried to avoid that... I see a lot of media that trys to cater to gamers doing that and I always found that cringy, the most recent offender i saw was glitch techs, they do that ALL THE TIME (and don't get me wrong, i loved that show)... This is due to me growing up in a rural city and video games not being popular when I grew up so it was always a 'weird' thing and I was 'the weird kid' who like it... So It's a personal thing, i'm not judging anoyone, and it's totally fine to do it, I just get embarassed for myself when I try it.
That being said, I do use some table top rpg jargon IRL, but that is mostly because my friend groups are entirely revolved around that... Se we often get one another when we say 'I just botched my DEX save' or 'I didn't spec my character for CHAR'
3) Anything else?
I would highly recomend you research gaming things by generation... As I mentioned above, my experience as a gamer growing up was a lot different than some younger folks nowadays... Diferent generations of gamers will have different priorities, likes and dislikes... Like I for instance can't stand lootboxes and excesive DLC, and the whole pay to play thing mobile games do, but a younger gamer might be totally fine with it.
I would also urge you to think carefully about what each game is targeting on people... Like a person whose favorite game genre is metroidvania or RPG (like me) will have a completely diferent personality from someone who likes FPS, the games themselves are made for different kinds of people, so different people like them... And being a 'gamer' doesn't mean you like every game ever made.
Metroidvania and RPG players tend to not mind graphics so much and are very throrough when it comes to exploration.
FPS players tend to care a lot for graphical fidelity.
Platformer players tend to care in great deal about mechanics and the deliberate use of them.
Puzzle players want to take their sweet time and not feel like you held their hands.
MMO players are veeeeeeeery patient, detail oriented, and will be okay with repeating content.
And so many other genres, like sports games, strategy games, betting games, party games... You name it...
Essentially, look for a game's main strenghts and say 'what kind of person would like this the most? And what kind of person would play this the best?' Remember, just because you're good at a game doesn't mean you like playing it... A musician could likely demolish most rythm games, but that doesn't mean they enjoy it.
Finally remember that there is often the unspoken rule... Don't hate the player hate the game...
Games (and particularly competitive games) have a way of awakening completely different versions of us... And that version is not us, it just a part of us... So a total cinamon roll of a person IRL might think gunning down civilians in GTA is fun, and that's totally acceptable and normal.
Morality in the game ≠ morality IRL
I would also encourage you to portray different types of gamers... Like... The stereotype for the word 'gamer' is either a super enthusiatic person who is WAAAAAY to into it, or an elitist nerd who thinks he is the absolute top notch person because he can speedrun mario without dying.
Those are tired old stereotypes... Not to say you can't make characters that fit them to some extent, but remember a gamer is a person too, they have a life that doesn't involve videogames.