Lookup values Read only

What would be the best way to add the Expanded fields from a look in more of a HTML way?
I want to show items related to a lookup(List A), But I don't want to auto fill more fields, cause I don't want to make fields on List B for what is read only.

I'm looking for 2 columns basically,
Column one would have a condensed Read only view for Fields pulling from LIST A.(Informational)
Column two would have the fields from the current list( List B) for people to adjust. (Actionable)

Dear @OPSPro,
I am not sure if I understand correctly, but you want to copy Extra fields retrieved with a lookup field into non-editable text area? You can use HTML control for that and jQuery to fill its values.

For example:

Field1: <span id='field1'></span>

Then, JS code to fill it:

$('#field1').text = value;

You can also use Additional fields from the Source list:

Thanks! I don't know why I couldn't see that in the documentation. but I see it now!
We have a ton of related lists/fields so Idk I tend to worry about performance when using native SharePoint lookups and related features. They have too many limitations.