Assigning Posts to Tags

Question

I have a website set up with the following example of posts, taxonomies and terms...

Custom Post Type A 

Taxonomy 1 
    Taxonomy 1-Sub 1 
        Tag A
        Tag B
        Tag C
        …
        …
        …
        …
        Tag GGG
    Taxonomy 1-Sub 2
        Tag A
        Tag B
        Tag C
        …
        …
        …
        …
        Tag GGG

Say I'm creating PostABC in Custom Post Type A, I can select or add any of the tags from Taxonomy 1-Sub 1 or Sub 2 but there are a LOT of options within those Subs.

How can I instead go to Tag A or Tag GGG and under the term edit screen, assign that tag to PostABC?

Is there a function to add that adds Custom Post Types into the edit page of a term as something I can select? I've tried to search but this specific instance isn't coming up no matter what I type in.

I don't think it would make a difference but I am creating these custom post types and custom taxonomies with ACF on Wordpress.