Thank you for your replies, I appreciate them very much.
I am keen to learn about the Edgerouter, from what I can see there is a lot you can do with it, but I do not want my learning to be at the expense of internet connectivity.
I have the Tp-Link set up exactly how I want it, I have the relevant ports open for my website and email server (using Ubuntu 18.04 server) and have set static IP addresses for all my computers (including the VM's). I am intimately acquainted the GUI and can make any necessary changes quickly and efficiently.
The Edgerouter is a level up from the Tp-Link and there will be a learning curve. I will make mistakes and it could be some time before I figure out how to undo what I did to regain internet connectivity. I run my business from home so I cant afford to not have internet.
Short of getting a second internet connection from my ISP and running a second ethernet cable from the ONT to the Edgerouter is there a way the two routers can be run side by side? This way I can fiddle to my hearts content with the Edgerouter without jeopardizing internet connectivity.