Beginners need to learn to point underneath each word as they read and understand that one word on the page corresponds to one spoken word.
Long, multisyllabic words still have one point each. When you are sure your child understands this, she / he no longer needs to point. You can then ask your child to ‘point with your eyes’. Eyes can move across the print more quickly than fingers. Your child will begin to read more fluently when fingers are not in the way.
Sometimes your child will ‘use your finger’ to help work something out. On longer books your child may need to keep track of the lines of print by moving a finger down the margin. These are both helpful strategies!