Hi!
First you need to decided what you exactly want to do.
If you aiming for tabletop experience with your friends then Game Master mode is your option. Its idea is allow you run tabletop like sessions with experience as close to real life as possible. For this you don't need any programming/art skills - all tools in game will provide you with everything you need to run a campaign and you need just to be a story teller. (i'm advising to see tutorial video or take a look on tutorial campaign). But this mode won't allow you to create standalone campaigns. Like in all table top rpgs you need Game Master to run it and players to enjoy it. To allow players and GM full freedom of choice this mode does not include triggers, script programming and explicit quests like in main campaign.
If you aiming for a experience close to Main Campaign of DoS 2 then "Divinity Engine" is your option. There you have full power engine allowing you to create new mods, scenarios and campaign which are can be played in standalone way, i.e. without you running it. This will require you to create your own levels with level editor, writing scripts, setting triggers and etc. I should mention that script language do not require you to be full power programmer, you can master it pretty easy and you also can alter already existing things.
You also can you Divinity Engine to extend GM mode with more level templates, monsters to spawn.
So all in all what you need to do is purely based on what you want to have in the end.