If I erase contents on old MacBook pro will it erase contents on new MacBook pro?

karen1239 wrote:

I'm giving away an older MacBook pro and want to erase contents but worried that my new MacBook contents will also be erased.

Before giving away your computer make sure you do this: What to do before you sell, give away, trade in, or recycle your Mac - Apple Support

If you're going to erase your MacBook, one of the first steps is to sign out of iCloud. So If you will erase the MacBook, you will only erase things that are locally stored, and not in the cloud. So you could erase the MacBook without risking files on your new MacBook