How to Check Open and Listening Ports on Linux | Ubuntu 22.04

Would be nice to highlight/enlarge what's being typed.

Noob here, working on a project entirely by myself. I've been trying to open port 443. I've tried various commands from various websites to try to get the port open but whenever I've used an online port checker it always says closed. I've asked my ISP for advice, but the person I spoke to there has provided bad advice in the past and has done so again on this occassion. Thank heavens then, that I found this video. Using the commands you've shown here I'be been able to prove that despite the commands shown on the websites I've tried so far, the 'port-closed' problem is with my Ubuntu and not some problem with my modem's configuation, so thank you for helping to clarify that.

Great channel and that's what I was looking for!
Subscription is set🤗

Exactly what I needed thanks!