Transferring Files from one external drive to another

I have an external SSD drive that is showing an error having something to do with the file system and a tree structure. I have purchased another external SSD drive. I want to transfer all the files from the old to the new drive. Then, reformat the old drive to see if the error is resolved. If so, I want to put some files back onto the old SSD drive and leave some files on the new SSD drive. What is the proper way (if any) to transfer files?

Computer: Mac Studio

OS: Sequoia 15.3.2

Old SSD drive: SanDisk Professional, 4TB

New SSD drive: Samsung T9, 2TB

Thank you for your time.

Mike