I have 30 flavors of pizza. Simple products. I need to register a product that let me combine up to 3 flavors on a pizza only .. hi, split a pizza in 3 flavors ... How to do this ?
I think you want to sell pizza where customer can choose 3 flavor in product at same time.
for that you can create custom option
other wise for one product one option you can use above answer and create configurable product
Yo can make a configurable product. In the magento user guide you can know how. http://docs.magento.com/m1/ce/user_guide/catalog/product-configurable.html
For more configurable product (like diferent size and flavours pizza) you can use the bundle product. http://docs.magento.com/m1/ce/user_guide/catalog/product-bundle.html