I can not upload music to my ipod

You are not providing enough info to help you:

What exactly happens when you try to sync?

Does iTunes see the iPod?

Was the iPod previous synced to another iTunes library/computer?

Have you successfully synced from this iTunes library/computer before?

If so have you done anything like update iTunes on the computer since it last successfully synced?

Do the songs play in iTunes?

Does any media now sync to the iPod?

Do you have the right boxes checked to sync?

iTunes: Syncing media content to iOS devices and iPod

Try syncing using the manual method

Managing content manually on iPhone, iPad, and iPod

You are not providing enough info to help you:

What exactly happens when you try to sync?

Does iTunes see the iPod?

Was the iPod previous synced to another iTunes library/computer?

Have you successfully synced from this iTunes library/computer before?

If so have you done anything like update iTunes on the computer since it last successfully synced?

Do the songs play in iTunes?

Does any media now sync to the iPod?

Do you have the right boxes checked to sync?

iTunes: Syncing media content to iOS devices and iPod

Try syncing using the manual method

Managing content manually on iPhone, iPad, and iPod

That means do yo have the right boxes checked to manually manage music:

Managing content manually on iPhone, iPad, and iPod

Again:

Have you successfully synced from this iTunes library/computer before?

Do the songs play in iTunes?

Does any media now sync to the iPod?

You need to backup the iPod to iTunes and restore from that backup since the iPod sees the reformatted computer as a new computer. You can only sync with one computer.

iOS: Back up and restore your iOS device with iCloud or iTunes

If all the synced media is not currently in your iTunes library than also do this

Syncing to a "New" Computer or replacing a "crashed" Hard Drive: Apple Support Communities