Armhole Band help

I am making a kimono and I have completed all of the parts, I am up to knitting the armhole bands but I don’t understand what they mean in the text below. If someone could just explain what this means and what I have to do that would be great. Sorry if the answer is really obvious to others but I’m really stuck.

Join fronts and back along upper edges to form shoulder seams. Tie a coloured thread of side edges of Back and Fronts 27 cm from shoulder seam to mark armholes. With right side facing up and using 4.5 mm needles knit up 114 sts evenly between coloured threads.

There is also a diagram/picture

Hi and welcome!
Once you join across the shoulders, measure down 27cm from the shoulder and mark both the front and back. Now open the two pieces up so that they lie flat and pick up 114sts between the 2 markers. That 57sts on either side of the shoulder seam.
Here’s a video for picking up and knitting sts if you need one:

Thank you so much!