Hello.
Products variations/selections available at one and the same products page is possible to get in Magento in 2 ways - custom options or configurable products.
Check here the comparison of them -
https://www.mag-manager.com/useful-articles/tipstricks/simple-products-with-custom-options-vs-config...
Custom options are easier to create, but using them you will not be able to track stock for variations of colors and sizes.
If you choose Configurable products, you will have to create all the unique combinations of options you have. Basing on your example (size 1-4), colour 1 (17 options) colour 2 (17 options) and then main colour (7 options) it will be more than 8 thousand products.
If you need to track stock and decide to use Configurable, you might be interested in the tool that allows to generate all those variations instead of creating them manually. You can do it using Store Manager for Magento application. It is paid, if you need it once or a few times, with 14-day fully-functional trial you can perform the task (you can download it from my signature).
Here is the article with video tutorial that demonstrates generation of associated to Configurable products in 2 clicks -
https://www.mag-manager.com/useful-articles/how-to/how-to-create-all-combinations-of-simple-products...
