How can I add a filter by tag feature to my theme?

Hi,

I’m hoping someone can help me with implementing the “filter by tag” function to this collection. The theme I’m using does NOT support filters so I know I need to code this in manually.

I see the drop down menu (circled below in red) but I cannot seem to add any options to this menu for customers to select. I want to add specific product tags so that the customer can select “2” for example to filter to only products tagged with “2”. I’ve been trying to follow these instructions https://shopify.dev/themes/navigation-search/filtering/tag-filtering but having no luck.

When I go to theme.scss.liquid, I see " Minimal | A theme by Shopify Built on Timber v2.0.0" if that’s helpful

Here is the link to access this collection. The example I have below is the first product. The collection is password protected, please use the below if you need to access

URL: https://www.thehappyisles.com/collections/database

log in: william@thehappyisles.com

PW: TempPassword2022!