Help with dec in a pattern

hello I am new to this forum and I am stuck … I would really appreciate some help as I am knitting to get over a broken heart, I am stuck on …

k3 k2togtbl, knit to last 5 sts, k2tog k3. This row sets the position of the decrease.

[COLOR=“Red”][COLOR=“red”]Dec 1 st at each end as set above of next 5 foll 4th rows, ending with a right side row -[/COLOR][/COLOR]

it then says work 15 rows.

I am stuck on the red part of the pattern …do I just decrease 1 at the end of each row for the next 5 rows …or is it more than that … I would appreciate any help or advice

Welcome to the forum!
The instructions are telling you to decrease at [I]each[/I] end on every 4th row. Repeat that dec 5 times. So you should dec on rows 4,8,12,16 and 20.
Remember that it’s 2 decreases per row.

Is it a triangle shawl or something similar?
The pattern is putting the decreases three stitches in from either end of the rows, probably to keep the edges neat and straight. Two decreases, then three rows that don’t decrease will ake a gradual slope to the sides.