Complete Novice to Netgear Wireless Extender EX6100v2

I have ATT-Uverse 1 gig wireless internet.  The router or modem (or whatever it's called) is in a back room of my house.  I want to add a doorbell camera at my front door; that camera needs a minimum upload/download speed of 1.5.  I cannot get the downloaded app to measure it to consistently meet that minimum.  When I spoke with ATT, they told me to buy an extender, because the problem is distance from the router/modem thing to the front door.  So, I got one at BestBuy.  I have plugged it in, halfway between the router/modem and the doorbell.  It has a green light and seems to be working--I get a high enough reading at the doorbell now.  But the extender came with a book of instructions about doing a bunch of other things.  My question is, is just plugging it in OK, or are my higher readings just a fluke, and I need to figure out a way to follow all those instructions in the booklet?  Anyone have time in your super-busy lives to respond to a grandma's likely dumb question?  Thanks.