No video that I know of but the flyer that came with it spells things out pretty well. You just need to do two things to make sure all will go smooth. One is get enough liquid into the cartomizer, if you get a little too much thats ok it will just leak a drop or two out the bottom of the cartomizer letting you know it is full. Two is start it without too much power, very short taps on the fire button while drawing will do this. I usually will take four or five draws with no more than a half second or so of power applied and in that time will begin to see wisps of vapor and a taste of the flavor. Once you have flavor and vapor its good to go time until the next cartomizer goes in then the same thing again to get it going.
On the liquids. You can use any liquid in a cartomizer tank though darker, sweet flavors will most often shorten the life of the cartomizer. Some folks also find particular flavors they like more/less in a cartomizer tank as it will present a different profile to the vape. This is very subjective making it a to each their own thing and something you will have to sort, fortunately cartomizers are quite inexpensive so risking one isnt the end of the world and you can also switch out to a different flavor. Complimenting flavors are easy to move from one to another like peach to watermelon and will even offer up some interesting transitional vaping. Even contrasting flavors can sometimes be fun like going from vanilla to orange. The new flavor will quickly replace the old one. There are a few flavors though that once in any kind of device tend to stick around, anise and cinnamon are a couple that come to mind.
Hope you enjoy your new tank, just remember this is meant to be easy. We have grown so used to how carefree our cartomizer tanks are that for us now vaping is just that instead of constantly trying to figure out why on everything, fill in the morning and change the battery when the light blinks... the rest is just vaping.