Site to Site VPN to UNIFI UDM Pro

Hello
I have a weekend house with a GL-SFT1200. Its an amazing powerfull small router.
I was trying to create a site to site vpn with open VPN client on teh GL router but it only allows with a config file.
Any ideas there how to config a Site to Site vpn to my unifi Dream Machine?

Regards

You can try the openwrt script