I'm glad you're finding the site helpful. Some of the questions will become clearer as you have the stitches on the needle but it's always a good idea to read through the pattern first.
For the decreases on each side of the back, the right side should be facing you on the left needle, ready to be knit onto the righthand needle.
For the front, you're at the part where you shape the armholes and divide for the neck. Follow the directions until you have the number of sts for your size on the righthand needle, then slip the next 2sts to a stitch holder (these are the two sts that you'll work when you get to the neckband). Now join and start knitting with a new end of yarn. You're dividing for the left and right shoulders so you can work each shoulder with a separate ball of yarn. You'll be shaping the deep V neck on this sweater.