Connect mikrotik with external squid

Hello.

I’d like to connect mikrotik with external squid.
My scheme of networks:
Mikrotik has LAN - 10.254.6.1/24,WAN - 172.16.0.1/24 и OPENVPN tunnel - 10.253.6.6/30.
Pfsense+Squid has ip LAN - 192.168.100.1/24, 10.253.0.1/16.

Now I write ip squid 192.168.100.1:3128 in brouser settings and it’s not conveniently.

They connected through tunnel. I need to redirect all http, https traffic to Squid.

Help me, please.