Hi HTP,
The below is what I use to merge various files together. In my example, the column "Barcode" is used, but as always, nomenclature can be changed to fit your desires.
CSVcombined = full_join(CSV1, CSV2, by = "Barcode")
Created on 2022-05-03 by the reprex package (v2.0.0)
This assumes you have already imported the files. I ususally do this manually since I run this quite often, and the file directories are never in consistent places.
Hope this helps,
Q