Can a 2008 bumper fits 2000 jeep

It will not fit, you will need to find something that is from 1996-2006.

Ok but why won’t it fit bolt hole to big?

For clarity, the bumpers from 2007 & newer Wranglers (JK) are not designed to fit on any prior models, like yours (TJ). I'm not exactly sure how the bumpers would align for bolts, as I have never attempted it, but I doubt it would be a direct fit, as they separate the aftermarket bumpers by year. I guess you could figure out a way to make it work with some modifications, but they are very different bumpers and it could be unsafe. Cosmetically, it would also look a bit odd, as the JK Wranglers are 6 inches wider than the TJs and your bumpers may stick out past the edge of the Jeep. At the end of the day, it won't be worth your time and effort to modify the bumper to make it fit. A google search for TJ Jeep Wrangler Replacement Bumper should yield you a number of bumpers that will perfectly fit your Jeep.