can i share my iTunes from my old apple id to my new one

I gather that you do not have your valuable content backed up to an external hard drive or other media? Please make a backup, and then you will not have to worry that something is going to erase your content.

You say "his new mac", "my new mac", and "the mac" so I am not clear what you want where. Items cannot be transferred between accounts. You can continue to use items from multiple accounts in various ways but if you want access to your old purchases you will have to continue to have access to your old/daughter's account.

There are many ways to share and use media from different accounts. The best will depend upon knowing exactly what you want in your new setup. Some examples are Music Sharing, Family Sharing and Home Sharing.

https://support.apple.com/en-us/HT201779 - about Music Sharing and Home Sharing

Home Sharing Support page - http://www.apple.com/support/homesharing/

iTunes 12 for Mac: Use Home Sharing to import items from another iTunes library - https://support.apple.com/kb/PH19614

iTunes: Setting up Home Sharing on your computer - http://support.apple.com/kb/HT4620

Understanding Home Sharing - http://support.apple.com/kb/HT3819

Distinguishing music sharing and Home Sharing - https://discussions.apple.com/thread/6056435

Music Sharing - http://support.apple.com/kb/HT2688

Family Sharing - http://support.apple.com/kb/HT201060 - "Family Sharing makes it easy for up to six people in your family to share each other’s iTunes, iBooks, and App Store purchases without sharing accounts. Pay for family purchases with the same credit card and approve kids’ spending right from a parent’s device. And share photos, a family calendar, and more to help keep everyone connected."

Sharing purchased content with Family Sharing - http://support.apple.com/HT201085 - "With Family Sharing, family members get immediate access to each others’ music, movies, TV shows, books, and apps, and can download them to their own devices any time they like.*" "* Not all content and content types are available in all countries. All family members must use the same iTunes Store country or region. Music, movies, TV shows, and books can be downloaded on up to 10 devices per account, five of which can be computers. Apps can be downloaded to any devices the family member owns or controls.

If you don't see your family's shared content - http://support.apple.com/kb/TS5449 Also: http://apple.stackexchange.com/a/146077 - quit iTunes Store and App Store apps and start again.

Which purchased content can I share using Family Sharing - Apple Support - http://support.apple.com/HT203046

Leave Family Sharing - http://support.apple.com/HT201081

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http://www.iclarified.com/41419/whats-new-in-ios-8-family-sharing -

Family Purchases and Ask To Buy

When a family member initiates a new purchase, it is billed directly to the family organizer’s account, unless the family member has gift or store credit sufficient to cover the entire amount. Once purchased, the item is added to the initiating family member’s account and shared with the rest of the family group. If Family Sharing is ever disabled, each member will keep the items they chose to purchase—even if they were paid for by the family organizer.