prefix delegation

My ISP is Telia, and I'm using these settings in IPv6: I have a /56 prefix, so I would want to give one subnet of it to Docker containers running on a virtual machine and seperate subnet for the rest of my LAN. How would I get this done on the router? I would rather use the router for this...

Hi everyone, This is my first post, though I've been using this forum a lot already as a great resource of information. Thanks to all contributors! The student village I live in recently changed ISP to one that does not give out public IPv4 adresses to each user, they are doing NAT instead...