I got a new laptop and I can't sync all my music onto iTunes without iTunes saying it will erase my songs on the phone, how do I fix this to where I can put all my music on my laptop?

If you do not have access to the iTunes Library on your Old computer... or its Backup...

See these 2 Links...

Syncing to a New Computer...

https://discussions.apple.com/docs/DOC-3141

Recovering your iTunes library from your iPod or iOS device

https://discussions.apple.com/docs/DOC-3991

If you do have access... See Here...

iTunes: How to move your music to a new computer

iTunes Music (purchased from iTunes): Downloading past purchases from App Store, iBookstore, and iTunes Store

Non-iTunes Music (CDs or Third-Party): How to use your iPod to move your music to a new computer

All music redownloaded will all be saved to your laptop.