Hi and welcome! I recommend you read/watch some of the sticky
threads at the top of New Members especially the Newbie Videos and and the thread with Library in the title which will lead to an illustrated multipart guide. That's best to get started.
And don't
buy anything at a mall, don't try any free trials, don't
buy anything from a fancy website if you don't know what model it really is, whether it's a good model, whether it's crippled to make refills harder, and whether you are paying to much. All ecigarettes that look anything like a cigarette are made in China by a handful of companies so there is no reason to pay too much for them. There are reasonable price US vendors for all good models.
And BTW after 5 posts/replies in New Members about about an hour, then you will be able to post elsewhere on the forum though this section is probably best for newbie questions.