I would appreciate some help

i am attempting for the first time to join knitting in the round left handed. my problem is in normal knitting you go from left to right and then at the end you turn but in the round you join and keep going. here is the problem i have no problem knitting but for some reason on row 2 you do 1x1 ribbing and i cannot figure out to purt. i have had to cast on 290 stitches and must be doing something wrong because i cannot figure it out. for anyone who has done this pattern it is the caprese tank from e-patterncentral.com any help is appreciated. thank you.

Here’s a video for the left-handed purl stitch. There are a few others online, too if this is not your style of knitting.

It should be very similar to purling back and forth. If it’s something about joining in the round that’s causing the problem, just post again.