One option would be configuring the SSH server to listen on port 443. Some proxies do not actually inspect the packets that are going through and just filter traffic based on the target port. Port 443 is used for HTTPS traffic, so such proxies will definitely allow it. If you are willing to sacrifice the possibility of hosting an HTTPS website on your Droplet, you can give that a shot. To do so:

1. Log in to your Droplet using the Remote Console in the control panel
2. Open /etc/ssh/sshd_config in a text editor
3. Uncomment the line # Port 22 by deleting the # and replace 22 with 443.
4. Save the file and restart OpenSSH: sudo systemctl restart ssh

That's not the best option but it's the quickest and easiest to set up. Another route would be setting up a VPN, but again, that also depends on how your proxy works. If it actually inspects packets and blocks VPNs, there's not much you could do:

• OpenVPN: https://www.digitalocean.com/community/tutorials/how-to-set-up-an-openvpn-server-on-ubuntu-16-04
• Algo: https://zeltser.com/deploy-algo-vpn-digital-ocean/

The university I go to blocks OpenVPN, but not IKEv2 which Also uses. So, I'd recommend spinning up a new Droplet to experiment with different methods and figure out what works best for you.