Ubuntu Server Setup / Configuration

Background: I want to setup streaming server and some server admin assistance. I have some technical skills, but am not proficient with Ubuntu. I have purchased a dedicated server via a cloud provider and have selected Ubuntu 18.04 as the OS. The cloud provider provides easy to install (automated) OS templates.

Responsibilities
⦁ Secure / harden the server (e.g., secure shared memory, add security banner login, restrict su access, install fail2ban, whitelist SSH ports, implement firewall rules / IP tables, disable unnecessary services). The extent of hardening will be determined through future communication
⦁ Other considerations that are not as technical: change root password, add user account, SSH keys, change SSH port
⦁ Install and configure VPN
⦁ Note: I also want to be educated during this process

Potential future work:
⦁ Install middleware software - instructions to be provided
⦁ Duplicate efforts on additional servers as I scale out
⦁ Setup backup procedures and routines

I would think this should be routine for a Linux admin, but like I said, I am not proficient on this topic. Thank you.

Note: The site required me to enter a budget so I haphazardly entered an amount.