[have MAC book]

Hello everyone! I read a few threads and thread Bitcoin core does not show wallet.dat balance after synchronization and rescan
And have almost the same problem. But I'm super not tech-savvy and have MAC book
So things that people suggested in different threads I don' know if I even did them. As I don;t have so many files when opening on mac bitcoincore.

So I have my old wallet.dat file from my old laptop (botcoin.core there is not opening - the app itself just I guess old version)
So I installed a new app on my new laptop. Waited a couple of days to synchronize with blockchain and then I tried to just copy and paste the wallet.dat file to the new bitcoin.core
I closed the app. Copy pasted and then opened and have an error come up with all wallet.dat files that I have

Error: Prune: last wallet synchronization goes beyond pruned data. You need to -reindex (download the whole blockchain again in case of pruned node)

What am I doing wrong? I don't even know what Prune means....

How can I recover my file, what steps am I missing?  

I know my key, I have the file, I know the address of my wallet. What is the best way to recover them? Thank you