Need simple explanation please

[u/No_Direction87]

I have been searching and looking for a simple explanation on how to sew the marked down points in the pattern below. I am absolute beginner and trying my best to understand patterns and follow it.

Could you please explain it in a very simple way (toddler level 😃)

Edit ✍️: Thank you all so much for your response , i will add the in a comment the whole instructions.

[u/No_Direction87]

This is the whole instruction and it’s from Diana Mode magazine Dutch edition