How to remove rows from one sheet of google spreadsheet that are present in second sheet of google spreadsheet?

Question

Google Sheets

Good afternoon. There are 2 sheets in google spreadsheet. Each sheet has two columns (A-name, B-phone number), the first sheet has 600 lines, the second has 100 lines. Almost all lines from the second sheet occur in one place or another in the first sheet. Attention question:
How to make a table in which there will be rows from the first sheet but without rows from the second sheet? In other words, how to delete rows in the first sheet that occur in the second sheet?

Answer 1

The easiest way is to color the duplicate lines in both sheets, and then manually remove the colored ones.
Menu: Format -> Conditional Formatting...

Answer 2

filter and unique