WooCommerce assistance

I am able to add subcategories to the shop, from within the wordpress dashboard, but when importing csv feeds, they’re automatically imported into the category that’s listed within the feed I’m importing. Is it possible to create subcategories for feeds after they’ve already been imported, or is this something altogether not possible?

I can’t figure out how to get the Dimensions under the additional Information for the sample “Rolo Chain in 10k Yellow Gold (1.9mm)” to change when selecting the chain size from the dropdown menu.
I was able to create the variables for the sample chain I manually posted, but I have no understanding when it comes to using the same variables for the remainder of chains I would be importing in bulk.
Also, would I need to manually post a different product and create the variables for each group of new items I import, for instance rings and bracelets sizes?

The part about “using your own CSV as a sample format to add the products and bulk import it is where I’m stuck. The column mapping is foreign to me. I can’t seem to understand that part and if that’s what can be done, to make importing in bulk easier, would it be possible to give me the instructions on how to do that? I’m a novice at this; I’m learning something new every day. Any and all help would greatly be appreciated.

As I’m working on the site, classifi-ads.com, I do have the wp-maintenance mode plugin activated. If you are willing and able to assist me, I would either have to create a new user and give you access to the dashboard, or disable the maintenance mode while this issue is being resolved.