How can I alter the Meta on my collections/all page for improved SEO?

[Eli90]

Hi,

I would like to change the Meta title & description of this page:

I would like to understand where this page is coming from :
https://sugarfreeeu.com/collections/all

It comes by default from Shopify and it shows all of my collections at once. I would like to add a Meta title and description, since it has a negative influence on my SEO.

Could anyone help? (using Dawn theme).