For those concerned about the legality or safety of ROMs, there are alternatives:
The N64’s hardware limitations—particularly its cartridge storage space (max 64MB vs. PlayStation’s 700MB CD-ROM) and lack of full-motion video playback—made porting Tomb Raider’s FMVs and high-res textures impossible without severe cuts. Core Design never attempted it. tomb raider nintendo 64 rom download
Here is the first hurdle for your search: There is no "Tomb Raider 1" on the Nintendo 64. For those concerned about the legality or safety
The original Tomb Raider (1996) was a console exclusive for the Sony PlayStation (it was on PC and Saturn as well, but not Nintendo). This is often where the confusion lies. If you are looking for the original game where Lara raids the tombs of Peru, Greece, and Egypt, you won't find an N64 ROM for it. Here is the first hurdle for your search:
However, the N64 did receive two titles later in the console's life cycle:
So, if you are searching for a ROM, these are the specific file names you should be looking for. But downloading them isn't as simple as clicking the first link you see.
Believe it or not, the best place to play classic Tomb Raider on a Nintendo console today is the Nintendo Switch. Aspyr Media has released remastered versions of the first three Tomb Raider games on the Switch eShop. These are not just raw ROMs; they have been updated with modern control schemes, updated graphics that you can toggle on and off, and trophy support. It is the definitive way to experience the original trilogy on a Nintendo system.