how do I install the SoftEther VPN Client and Server Manager for Ubuntu 20.04? I am not looking to setup a VPN on my machine. I want to connect to other servers. Thank you
I would not suggest setting up SoftEther Client for Linux since it could be difficult for new users. I would suggest using L2TP/IPsec, SSTP, or OpenVPN as a client for SoftEtherVPN (If you need to set a mac address for a static IP for the user, you can do that within the notes section of the user account). If you really need the SoftEther client, then this should help you. But I'd suggest getting the client from softether.org.
You can get the VPN server manager up and running on your system by downloading the windows version in zip form. You can then extract it and run it mostly without issues via Wine. (That's how I do it at least)