Yes, you can do this, but in a much better way than it is implemented in Excel. It is implemented in a database-like way:
Simply change your field into a single-select or multiple-select. When you enter the field, just start typing. If your value already exists in the matching results, just hit return to accept it. If your value doesn’t exist, just hit return anyways and it will get added to the list for the future.
There are several areas throughout Airtable that work like this. For example, linked fields work the same way. Just start typing and then hit return to accept the matching linked record. If you hit return when no linked records appear, it will create a brand new linked record for you based on what you were typing.
(Also, on an unrelated note, as one of the original people in this thread was looking for, you can do a simple copy-and-paste across rows/columns by dragging the lower right corner of the populated cell across empty ones. Airtable won’t alter the values as you paste them — it will just paste them.)
