Unable to set dual interface

[df54ds]

I started configuring my cluster last with Proxmox planning to prepare my Home Assistant server (and others to come) while my new place is being built and for now I'm not able to put my server close to my router. Since the problems with Wlan aint a big deal, I'd like to let it working thru it while still adjusting things instead of relying only in ethernet connection. Furthermore, I can follow some tutorial about command line codes and it's application to setting my network, but don't know much about what I'm doing.
By now I was able to connect my server to my network following this video, resulting in the scenario below:



After that I edited /etc/network/interfaces adding these lines (as seen here)

post-up   echo 1 > /proc/sys/net/ipv4/ip_forward
post-up   iptables -t nat -A POSTROUTING -s '10.10.10.0/24' -o eno1 -j MASQUERADE
post-down iptables -t nat -D POSTROUTING -s '10.10.10.0/24' -o eno1 -j MASQUERADE
post-up   iptables -t raw -I PREROUTING -i fwbr+ -j CT --zone 1
post-down iptables -t raw -D PREROUTING -i fwbr+ -j CT --zone 1

Besides, every time I restart my server it loses it's Wlan connection and I've to start it again with:

wpa_supplicant -c wpa_supplicant.conf -i wlxxxxxxxxx1 -B -Dnl80211
dhclient wlxxxxxxxxx1

After that if I try to access 192.168.100.98 I'm able to reach the server while connected to both Wlan and Eth and thought that was using Wlan, but after removing my cable I'm unable to reach the server. Am I doing something too stupid or that is a way I can follow to fix it? Which steps I'm missing?