Restricting Apple ID purchases to free stuff only

I've given my 9 year old daughter an IPad for Christmas. I'm confused about how to set it up with regards to using my Apple ID, or creating a separate AppleID for her. I've read some things about Family Sharing, but it doesn't seem to address what I want to do.

What I'd really like is for her to be able to download anything she likes from ITunes or the App Store as long as it's free without any need for me to authorize the download. However, for anything that is not free, I want to be the one who authorizes this with some kind of approval/password.

Can anyone please tell me if this type of setup is possible?

Thanks in advance

Dave B