Generally almost in every online shop we can see product variations showing as dropdown. But these dropdown could be shown as table.
Before create variations table you should know that
If select Variation product, you have to confirm, your all Variation is configured properly. Such: there will not support "any attribute" option for variation. eg: no support "Any Size" type variation.
And if enable Variation product, Some column and feature will be disable. such: Attribute, category, tag Column, Advance Search box.
To create a product variation like above screenshot. Lets follow below this steps:
Click on "Basics" tab. Spelldown and you will see "Product Type (Product/Variation Product)" . From there select "Only Variation Product".