The numbering should give you a hint on where to start, buddy.......
But like others said, it doesn't matter. RE7 has a couple teases about earlier games, but it doesn't really spoil or make any obvious references, except for maybe the very end of the game. But even that is very open-ended and confusing, hardly something that would even be considered a spoiler for older games.
So if you want to play them in order, just because, then start with the original, and the GC/PS4 versions are better than the original, since the original RE is outdated (still a lot of fun though).