Hi there,
No problem :)
The JR Pass allows unlimited travel on all JR lines so it will cover all of your journey on JR lines during it's validity period. If you are going directly to Kyoto from Narita and then back to Narita from Kyoto over a 9 day period, you'll need to look at a 14 day pass to get full coverage which in your case is not recommended without doing further travel as it will not be cost effective. Bear in mind that the 7 day pass can offer great savings, but you need to be doing the travel to make it worthwhile - at least spending ¥28,300 on individual JR tickets.
To use a JR Pass you need to first purchase it before you arrive in Japan (the nationwide pass is not available to buy in Japan). On arrival you activate it at a JR counter, and from that point on you can walk through all JR ticket barriers just by showing your pass. You do not need to purchase tickets for travel.
The only case where you may have tickets is where you make seat reservations. Reservations are free for JR Pass holders (normally a charge is applied), and you can make them by visiting a JR ticket office and specifying the train you'd like to use. You will receive a seat reservation ticket which you can then use on the train to find your seat.
There are so many bullet services running on the Tokyo to Kyoto route that it is extremely unlikely you will not be able to get a seat. If that does happen you can simply wait 30mins for the next Hikari bullet.
Hope this makes things clearer. We have explanatory videos here and here with more information that may also be helpful.