I would like to host a home server that some services are able to be access externally.

I did port forward and dmz, I wasn't able to get them working.
I'm wondering does unifi allow such function or do I need to pay unifi to unlock certain server hosting functions?

Which unifi package are you on? Suspecting that you do not have a public IP address (behind CGNAT).

Thanks for the reply.
I'm on unifi home 100mbps.
Residential internet.

Mind telling me what is CGNat?

In my work place I can know my public iP and easily port forward stuff for external use. For my house router the public iP display seems to be different from whatsmyip.com

It seems NGrok is able to bypass CGNat. Thanks for the help. I will try in my end.

if your ip address is behind CGNAT, cloudflare zero trust able to bypass too

First of all you need to ensure the correct Port Forwarding and the corresponding Server's IP Address is correct.

As you did not mentioned the services/server OS, I assumed you are running on Windows OS.

For Windows OS you need to ensure the built-in Firewall have the corresponding Port allowed access on both the Incoming & Outgoing policies.
The same goes for Linux OS too.

Putting your server on the DMZ is NOT recommended due to security concerns, unless that server doesn't contains any sensitive data. Most common use for DMZ is a Proxy Server like NGinx, Load Balancer etc.

If your home internet (presumably Unifi), then high chances you are running on Dynamic IP Address, so it is recommended to use a Dynamic DNS Service such as No-IP, DynDNS etc. This way you just need to remember the name instead of IP Address, and each time the IP Address changes the new IP Address will be automatically updated into the DDNS accordingly thus maintaining an always available access. Oh, you need to install their Update Apps, but most home router nowdays support No-IP so you can just configure the update inside the router instead of using their Updater Apps.

Hope this helps...