No access of HA via IP of virtual machine

I installed ubuntu 20.04.3 LTS on my old laptop. Next I followed the instructions of a youtube video " How to Setup Home assistant on Ubuntu (supervised) from scratch as virtual machine (KVM)".

Everything seems OK, except that I can’t access my HA via my Windows laptop on “” (Virtual Machine IP Address)
I can do it on (address of Ubuntu machine).

I did his instructions :
iptables -I FORWARD -o virbr0 -d -j ACCEPT
iptables -t nat -I PREROUTING -p tcp --dport 80 -j DNAT --to

What did I wrong ?

The iptables lines effectively forwards port 80 from the host to port 8123 on the VM, which is the actual port on which HA is listening.

So I don’t have to change anything, everything is normal ?

Here is an alternative writeup that shows how to install and boot a Home Assistant image as a VM running on QEMU/KVM with Ubuntu: