Product Variations/Options help

You can set a specific combination of attributes for each variation. For that combination, you can assign an SKU/part number.

Screenshot: https://cld.wthms.co/HND4Lj

For details, see https://docs.woocommerce.com/document/variable-product/#manually-adding-a-variation

You have full control over this from the back end – you can decide which combinations you have available for sale and manually create each of them.

To prevent them, simply do not create them.

The amount of product data including attributes, in theory, can be an unlimited amount. But bear in mind that the more data you add the more server resources the site would require to operate and load content from the database.

With attributes and variations, there is a default limit of 50 per product for AJAX loading on them.

That can be increased with a custom snippet if required: https://gist.github.com/claudiosanches/6f91ad228c2176b986b2

If you find the number of variations you can add to the product is limited, you can use some code like this to increase it:
https://www.proy.info/create-more-than-50-product-variations-in-woocommerce/

You’d place it in your theme’s functions.php file.

Or it can be easier/safer to use a plugin that handles it for you, like Code Snippets: https://en-ca.wordpress.org/plugins/code-snippets/