Do you mean "slip the first stitch purl wise"? If so, that means slip the stitch to the right needle by inserting the needle through the front loop from top to bottom, then the yarn to the back and continue knitting.
Probably means Purl, Purl
P3 means to do 3 purl stitches.
Purling is knitting the purl stitch.
Usually in knitting instructions, the letter P stands for purl.
It means "wrong side". In a stocking stitch, the purl side is the wrong side.
Knitting.
P2 means purl two stitches as K2 means knit two stitches.
it simple means put your needle into the next stitch as if you are going to purl and do what ever they say
One can learn how to knit and purl from videos on YouTube. This is a good way to learn because one can actually see how to do it rather than just following instructions. Vogue Knitting and Knitting Help also help one learn how to purl.
There are several sites that offer tutorials on how to get started at a purl stitch including Knitting Help and Knitting Daily. One can also go to a book store such as Barnes & Noble and read a knitting for beginners book.
slip 1 - insert needle into stitch as normal then just pull it off the left needle onto the right without knitting or purling it
P2tog means to Purl 2 stitches together.