There is no decent home kit.
You need a card to use a professional trade shop, get a good LED light box (preferably with a removable base so you can also do your toes), and good quality gels that will cost at least £8 each. You need base (builder), colour (builder), top coat. Builder gel is good if you have weak nails and do not even think about fancy add ons until you are any good at it.
Gelling to your cuticles is probably the biggest issue. To learn how to do it properly, get some cheap gels and keep practising until you learn how to manipulate the brush properly, with gels you tend to push rather than pull (hard to describe but pushing towards the cuticles rather than pulling away as you do with traditional polish). As my sister says (qualified BT and major chain spa manager) if its sits still, paint its nails and if it doesnt, knock it out and then paint its nails! She has been doing mine for years but still makes the odd mistake.
Doing your own nails, if you are no good at it, can be an expensive mistake to buy all of the proper kit. So rather than doing your own, maybe try a couple of new places first and see how it goes.
If you are determined to try, the biggest thing is to not overcure. It will wreck both the gel and your nails. If it says 30 seconds, cure for 30 seconds! Oh and keep the gels out of sunlight and if they are a bit thick, warm them up, they paint on better if they are warm.