If you have no gear then I think you should relax about background checking every single option. Pick a camera you like and gets good reviews (I would go for a good second hand unit, I did not do this when I started out but looking back etc). Pick up the kit lens with the most range and try out actually taking photos and not worrying about numbers. In real terms a kit lens is a relatively small investment and some of the lenses you ask are bigger investments. A kit lens will always be handy to have and with this lens you can find out what you like in terms of focal lengths and its limitations. If you end up liking taking pictures of stationary objects at daylight it may end up being all the lens you will ever need. Focal lengths, aperture sizes and all that really can only be explained when you have a visual example to compare with. Too much research will kill the fun. Buy some kit and take some shots