How to link my iPhone wjth my daughters IPad

You may find this information to be helpful with setting-up an AppleID for a minor (all Users should have a unique AppleID for use with their devices) and in considering appropriate controls:

Apple for Kids - Official Apple Support

Help your child set up an iPhone, iPad, or iPod touch - Apple Support

Family Sharing and Apple ID for your child – Apple Support

Use parental controls on your child's iPhone, iPad and iPod touch – Apple Support

You might also consider using the ScreenTime controls for the devices of the iPads - setting the ScreenTime passcode to something that only you know.

Use Screen Time on your iPhone, iPad or iPod touch – Apple Support

Set up Screen Time for a family member on iPad - Apple Support

I have a game and I want to have to data on my iPad to be on my phone