Unable to re-install music library after an external SSD crash and burn.

Hello everyone - I'm really sorry if this is a straightforward issue and I have checked several threads to see if I could resolve this myself but nothing seems to sort this out. I'll try and set out the issues in as much detail as possible and if there's extraneous information, please go ahead and ignore it! I'm very new to support threads as I\ve never really experienced too many issues with the previous tasks I've carried out and also I'm bloody old so be gentle.

1) I have a 2020 iMAC 27"

2) I have a large (relatively) music library which mostly consists of CDs previously burned onto prior computers via iTunes.

3) when I bought this computer I realised that I would rapidly fill up my drive with vids and Logic Pro music that I started making when I bought some synths so I transferred my music library onto a Sandisk 1Tb SSD drive attached to the desktop via a USB c cable. So my music library was moved over there.

4) My son also uses my computer and had a naughty habit of pulling out cables (and drives) without ejecting properly etc

5) for some reason, my Sandisk SSD recently failed - kaput, completely unusable - I tried 'first aid' all the recommended actions using disk utility - nothing helped.

6) No problem - I thought I can just buy a new SSD and download the backed up music via iCloud back onto a new drive.

7) so I tried to do that and I've hit a problem - whatever I do - creating a new library or re-locating an old library back onto the new Crucial 1Tb drive, I get the same error message when I click on a song in iTunes - "*****. [song} " could not be used because the original file could not be found. Would you like to locate it?.

So I went through the Cmd - I routine and tried to locate the song - then tried to copy over the location of the library based songs over to the new SSD>

It doesn't\t work, but weirdly, if I cancel the "cannot locate" error message and wait, the song starts from somewhere and then carries on as if nothing had happened.

I just want to move my whole music library over to the new Crucial drive but this is really really frustrating. I've sorted the photos app which was very easy - just downloaded from iCloud- but the music is proving too much for my limited skills.

Just for background, I've had four Macs going back to a 2005 G5, which was the basis for the original CD burn - it's around 450 CD albums plus about 200 downloaded songs bought from iTunes over the years.

Please can someone help a very frustrated 53 year old !!

Love from Yorkshire, England.