Lives - don't feel daft at all. It's really quite complex & difficult when you haven't been shown for real.
If you have a vaping shop near you it is really worth popping in, with your kit & having a chat to them & buying some juice or a new battery or something off them. It may cost you a little more than on line but you will get so much help & almost certainly the chance to try a few flavours.
I was in my local shop the other day & the owner was telling me of someone who came back in saying they couldn't get their kit to work. Turned out they had charged the battery, put the tank on & then taken the tank off & were trying to puff on just the battery!!
She (the owner of the shop) is lovely & has endless patience with showing people how they work.