Setting up Tailscale magic DNS with Opnsense and nextdns

[7myths]

 Hello guys,
I am very new to Opnsense and Networking in general. Except some basic concepts. I am using proxmox to virtualized opnsense.
Proxmox server is connected to a router with ip 192.168.x.x
Opnsense has DHCP server 172.0.0.0/24 with no VLANS

I have successfully setup Nextdns in Opnsense using unbound -> dns over tls.
I was also able to setup tailscale on Opnsense with advertised routes.

My questions are

• how do I use magic dns with my current setup so that I can access my current hostnames when connected to tailscale and nextdns.
• How do I add hostname for Proxmox in Opnsense so that I can use it on my local network as well as with tailscale magic dns.

I am very confused about dnsmasq and unbound in general and right now I am wondering even if its a right approach. I would really appreciate any help simplify this.
I was trying to achieve something like this: https://www.youtube.com/watch?v=Uzcs97XcxiE