Please read the first thread in this forum.

First, read the sticky thread on this forum, regarding game-specific questions. Second, you want to direct this question either here: https://www.speedrun.com/doom_64_2020/forum or here: https://www.speedrun.com/doom_64/forum

It looks like this question has already been answered on the forums. This post suggests that the PC version of Doom 64 (assuming you're not emulating) was released in 2020, in which case runs would go on the Doom 64 (2020) leaderboard.