From the ‘Other Settings’ tab, you can find the option to hide the product prices and Add to Cart button.
You can choose to hide one or both options options, for ALL the products in your shop. That way you can show only the Quote button and let your users submit a quote request.
Go to YITH Plugins > Request a Quote > Other settings and check the options based on your needs.
These options remove the price and the ‘add to cart’ button on all products.
If you want to apply these options to some specific products, please check out the integration with YITH WooCommerce Catalog Mode plugin, where you can manage on which products to show/hide the ‘add to cart’ button and price.