From a "work", can I add the LCC catalog number?

If I know a Library of Congress Catalog number for a book, say
67-13778 for:
https://www.librarything.com/work/128872/workdetails/197975657
The Awakening of Faith: Attributed to Asvaghosh

Is there a place I can record it?

If I have a choice to grab a book from Amazon, Overcat or the Library of Congress,
what's the best guidance on which one to pick? Is there any sort of "merge" feature where the knowledge from all the catalogs can get combined?

Avoid Amazon if you can. They have a lot of ratty data.

I generally start with Overcat, as it will return books entered from a variety of libraries. LOC is good, particularly for older books published in the U.S.

If you don't have the book in your library, no, you can not add an LCC to a work.
If you have the book in your library, then you can edit to add it to the book.

Also, what >2 lilithcat: says

Actually, you cannot edit even your own copy to add the LCCN. The only way to add that to the work is to enter from a source that includes it, so if you want that, you should enter using LoC as your source. Also, of course, if you have an LCCN, you know they have catalogued it.

Overcat includes a lot of information from many libraries, so it is a good place to try first.

What I'd like to do is merge these sources, in particular to tie the LCCN to the ISBN.
I see that's not possible, too bad.