When you increase or decrease a product quantity on the single product page, you will notice that the price does not increase or decrease in accordance with the quantity.

With the help of the Min Max Step Control Plugin, you can do that by just following a few simple steps.
Access your WordPress dashboard,
Negativation to WooCommerce >> Min Max Step Quantity.
On the You will see a “SETTINGS (UNIVERSAL)” section,
you will get Price multiply by quantity option.
You have to click on the toggle bar to turn on this option.
After that, click on the SAVE ALL button.

Now your customer can understand how this product will cost after increasing or decreasing quantity.