First post!

I have a spreadsheet with many rows and many columns where I want to delete entire rows based on a criteria to be found in one specific column. The column with the criteria to be used is sorted therefore all of the rows with that criteria are grouped.
In previous attempts to delete using information from previous posts, I ended up skipping rows and only deleting half of what I need to delete.
Do you have an idea of what I can do?

Thank you in advance for your help and expertise.