Customizing woocommerce

This is the CSS from the Twenty Twenty-Three theme that defines the font size for the price on the product page:

.woocommerce div.product .entry-summary .price,
.woocommerce div.product .entry-summary .woocommerce-Price-amount,
.woocommerce div.product .entry-summary del {
  font-size: var(--wp--preset--font-size--large);
}

To change the size to another of the theme’s font size, change the “large” part of the size variable to either “small”, “medium”, “x-large”, or “xx-large”.

For example, custom CSS to change to “small” size:

.woocommerce div.product .entry-summary .price,
.woocommerce div.product .entry-summary .woocommerce-Price-amount,
.woocommerce div.product .entry-summary del {
  font-size: var(--wp--preset--font-size--small);
}

The custom CSS can be added in the “Additional CSS” section of the old style customizer. To access this, add customize.php to the end of your dashboard admin URL, e.g. https://www.yoursite.com/wp-admin/customize.php

Can you please provide more detailed information about “all the prices”, as there is usually just the one price displayed at any one time for a single product (without variations).

Products with variations usually only show the price range below the product title and then the variable price above the add-to-cart button when the variable is selected.

Do you mean you want the main price below the title and the selected variable price to be different sizes? Or something else?
Would you be able to provide a link to one of your products so I can take a look and advise further. Thanks.

Thanks I see it now in the bulk pricing table from the Discount Rules and Dynamic Pricing for WooCommerce plugin

This custom CSS should do it:

.woocommerce div.product .entry-summary .wccs-bulk-pricing-table-container .woocommerce-Price-amount {
  font-size: var(--wp--preset--font-size--small);
}