i saw there’s a requirment for intalling jetpack is needded ubuntu 14.04,but i didn’t have a computer with that,any other way?
No, you need to get a desktop computer capable of running Ubuntu 14.04 or 16.04.
A regular computer with a second hard disk (for dual booting) is generally a good option.
If you are willing to just flash and not use JetPack (or its other features), then you can use any x86_64 Linux.
so it’s fine to use ubuntu 16 for intall jetpack as a host right?
Many people have reported this works, but may have a package or two which can’t be installed to host. It isn’t supported, but probably will work for everything going to the Jetson.