Apple IDs cannot be merged. She can put the photos into a Shared Album and send them to her personal Apple ID using iCloud Photo Sharing: iCloud Photo Sharing - Apple Support
For her Notes, she can go to the Notes app on her work phone, and while displaying the list of the Notes she wants on the new Apple ID, she can select Edit, then at the bottom of that screen select "Move All". She can then Move all of her iCloud Notes on the Work phone to the Notes folder under the "On My Phone" section.
Then she can sign her Work ID out of iCloud on the work phone, sign in her Personal ID into iCloud, open Notes, select the On My iPhone Notes, select Edit>Move All and move them into iCloud Notes. As long as Notes is selected under Settings>her name>iCloud, they will then sync to her iCloud account once she moves them.