At the same time building ready to assemble cabinets can actually be quite fun and rewarding helping you to get the feeling of being successful with DIY while at the same time meaning there's no risk of the cabinet not being structurally sound.
Before you begin with your ready to assemble cabinets you should find you have everything you need already in the box – most flat packed furniture includes the basics such as the screwdrivers and alan keys to fit the specific screws and bolts. You might also get some strong adhesive if there are pegs to be placed in the construction of the cabinets. However it doesn't hurt to keep a spare tool kit around just in case there is anything else you need and just in case you can have more success with a better screwdriver etc.
Another tip is not to empty out the screws and other items yet. These will likely come in small transparent bags and you are best off keeping them in these as it will mean that you have them labelled.