Do I need the gateway or not? If so, where is it?

A while ago I used whonix.
Back then I needed two VM’s. One for the gateway and one for user operations.

I can no longer find a downloadable gateway VM for running whonix on virtualbox. But amidst the documentation I found a snippet of information saying that only one ova needs to be downloaded and run.

When I load the ova and run whonix I cannot connect to the network.

A dialog comes up saying:

ERROR: Tor Connection Result: 
Tor's Control Port could not be reached! 

Troubleshooting: 
- Confirm that Whonix-Gateway is running. 
- Run systemcheck on Whonix-Gateway and confirm success. 
- If you're running multiple Whonix-Workstations simultaneously, confirm that separate IP addresses are configured (see https://www.whonix.org/wiki/Multiple_Whonix-Workstations). 
- Rerun systemcheck here in this Whonix-Workstation. 

(Technical information:) 
(tor_circuit_established_check_exit_code: 255) 
(tor_bootstrap_timeout_type: ) 
(tor_bootstrap_status: ) 
(check_socks_port_open_test: 56) 
(Tor Circuit: not established)

So do I need a gateway VM or not?
If so then where do I find it?

If not then how do I get on the network when using whonix?

Needed.

Installation as per usual.