If I recall correctly, here are some vague tips for Civ 6 (I'm not great at the game, but I have won a few matches):

Conquest and warfare are legit tools but you need to know what you are doing. (Which you dont so you will probably fuck it up) Try to get a second city out very early, around turn 20 to 30, not later. You probably should get a 3rd and even more cities over time ( I usually go for 5-6 in my games throughout the game) Try to settle next to new ressources you dont control at the start of the game. Oh and settle next to rivers or next to the ocean.

It might take a few games to get the hang of it, but barbarians aren’t that hard to deal with. Try to stop barbarian scouts from reporting your position to their camps that helps a lot. Honestly, I’d just recommend fucking around and getting a feel for the game.

Rome with Trajan is a decent beginner CIV.

Even if you dont wage offensive wars you want a small military or the AI will declare war on you . Different civs have different weighted AIs I think so - some leaders will be more likley to be aggressive etc.

I would recommend making a beginner thread in the Hexbear gaming comm. Im sure there are CIV6 players that are much better than me that can give you advice.

I might have time to teach you the game if you are really interested send me a dm if thats the case