There is a difference of opinion on the long tail cast on. Some people say that the long-tail cast on should count as a row when working stockinette stitch. Others treat the cast-on as just a cast-on and count the first row of the pattern as the first row.
I happen to be one who doesn’t count the cast on as a row.
As for the right side, or wrong side, your pattern should tell you if the first row is a rs or ws row.
If you’re working st st, you can purl the first knitted row and call it row 2, or just knit the first row. It really isn’t that big a deal for straight stockinette.
Personally if a pattern says to cast on and then knit X number of rows, I do just that.