In the patterns of The Dutch pattern farm, there are multiple layers. There is a layer for each size and a seperate layer for the seam allowance of each size.
Follow the directions here below to see how you can use these different layers. Step 1: Open up your pattern
Step 2(optional): Scroll down past the direction pages to the first page of the sewing pattern
Step 3: Click on the layers button
Step 4: Select the pattern name at the top of the column, to make all layers visible.
Step 5: Select the prefered layers. In the original pattern file, all seam allowance layers are invisible and only the basic pattern lines are shown. You can keep it like this, but then no seam allowance is added to your pattern, and you will need to add it yourself. (In the pattern instruction is written how much seam allowance is added to the seam allowance layers of the pattern) By clicking the the eye icon on or of, you can make the layers visible or invisible.
You can choose to make all layers visible, so seam allowance is added to each size and all sizes will be printed out. But because this will show a lot of lines on the pattern it might become a little difficult to distinguish the different sizes from eachother
Or you could only select the one size you will use, and choose to add the seam allowance layer to that size. To see which size is best to use, go to https://www.thedutchpatternfarm.com/size-charts to find the size chart in centimeters and in inches, with additional guidance on how to use them.
After selecting the prefered layers, you can click away the layers column and go ahead and print the pattern.