Why does my VPN keep saying connecting?

I am trying to use a VPN on my mac. I have set the Network.Enabled to true in the System Preferences. Whenever I connect to the VPN, I keep getting an error message "Connection could not be established with server".

In the Network preferences, it says "Connecting." and when I go to "VPN Connections", the status is "Connecting" Also, under the Internet Options > Connections > Lan Settings > Internet Protocol > Obtain an IP address automatically, it says "Disabled (Not available)". This is because you are trying to use a network protocol that the OS does not understand. There's no VPN protocol defined on Windows by default, so your VPN connections must be built on top of PPTP or L2TP. You can find a good explanation of VPN protocols here:
Note that I'm not 100% sure that what I said is correct, but it's the best explanation I can think of. MacRumors attracts a broad audience. Of both consumers and professionals interested in. The latest technologies and products. We also boast an active community focused on purchasing decisions and technical aspects of the iPhone, iPod, iPad, and Mac platforms.

Why isn't my VPN connecting on my iPhone?

I use VPN on my windows laptop and iPhone. Both of these are in a Windows Subnet. I've tried both ExpressVPN and PrivateInternetAccess, with both of these connections work on my laptop however only PrivateInternetAccess has an iOS port. Both VPN's allow to connect but in order to get connected the VPN must be set to automatically connect. How do I fix this? I've made sure that my iPhone is registered on my PC that I'm connecting from and I've added my username/password. (I use PIA).

From your question it sounds like you can access from other devices to your VPN host on the same subnet.