How its works and How to use Framed-ip-address

Hi, I successfully installed freeradius on Ubuntu 18**. I am using PPPoE server in mikrotik. I want to control PPPoE user ip address. Only match ip address, username and password can connect with network. Is this even possible? Also, I want to know about Framed-ip-address and how its works with freeradius. I searched google but not found my need. Thank you :) Sorry for Bad English.