I have a question, I want to do a speedrun with an emulator and in the rules it does not say anything, that means that it has to be a console version or is there an emulator allowed?

pd: the speedrun I want to do is for dreamcast version ,i forget to put in

If you check the Any% - Kid Mode category for DreamCast (DC), you'll see that there's already an uploaded, verified run that runs on emulator, so I believe you're good to go on that front.

That being said, you might want to specify which emulator you're going to use, given that some emulators aren't as accurate as others. I don't know much about DreamCast emulators myself, so your best bet would be to ask around to the folks at the discord server: https://discord.gg/XDKvnpa

PS: If any mods read this, perhaps it'd be nice to also include the link to the discord in this leaderboard's menu.