Someone knowledgeable will eventually come along with a link. Until then, if you're interested in a speedy solution then a quick Google search will set you up nice.
How or where can I download chess games databases...
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Here's something that might be of interest to you.
Mar 14, 2020
0
#5
WSama wrote:
Here's something that might be of interest to you.
I'm not sure, but I think that one may be the one with LOTS of duplicate games. It might be more trouble than it's worth. I think the guy merged several databases and didn't even know that he had to remove the dupes. 
Mar 14, 2020
0
#6
FWIW, I still haven't tried this one yet. (I don't use game databases much.)
It's in Scid format, so you'd have to convert it if you need a different format.
https://www.chess.com/forum/view/chess-equipment/caissabase-3-9-million-games
so that I can use 'em in my Stockfish program? Mac user, here, by the way.
Cheers