Docker VM VLANs

I have proxmox setup with my only network interface set to vlan-aware bridge, and then I have sub-interfaces on the bridge for proxmox’s web IP as well as a couple vlans for other virtual machines. I have setup a Ubuntu server VM and installed Docker along with Portainer in the VM. I initially made the VM network proxmox’s bridge interface with a tag of 2 so I could get everything setup and portainer accessible through the web. I did that and eveything is working ready for me to setup VLANs. I want my Ubuntu server to have a static address in vlan 2 so I can access portainer, but I will also need to have one Docker container use vlan2 too with another IP in vlan2 net. All other containers in Docker will use vlans 5 and 6. How do I use netplan to do this inside Ubuntu? I have read you can do vlan tagging, or you can set multiple IP’s on the same interface in Ubuntu. I am not sure which is better for my situation, or even how to use Netplan to do what I need. Everything I have found online gives the interface an IP and then adds vlan IP’s to it. Why would I not make the interface a bridge and then make the subfaces with their respective IPs like I did on proxmox?