Where should I add the settings_schema.json code?

[M053b]

Thank you for the code for the shopify filters, I was trying to implement it in my shop but I don't know where I should add the files (kinda of a newbie).
I was vaguely following this help thread: https://community.shopify.com/c/Technical-Q-A/How-to-add-collection-filters-code-in-the-right-places/td-p/517773 but I couldn't seem to figure out where I should add the settings_schema.json code, I thought it was supposed to go in the templates folder in the collections.liquid file but the original file has the .json extension so I don't know, any help?