When you weren't using Facebook, can you access normal pages like CNN, CBC, etc. while you are on Koodo nett

Yes I can, its only on click through links. like a link on facebook or a link in bio on instagram etc. 

If so, the Facebook app could be the culprit. https://www.androidheadlines.com/2021/06/facebook-now-doesnt-let-you-open-links-in-third-party-browsers-by-default.html

It wanted you to stay in the facebook app, and if the browser within the app had problem, users would be in trouble.

Anyway, I assumed you didn’t restrict data usage on facebook or some certain browser in the phone?

There are also apps that won’t work for me when I’m on data, and they are not affiliated with instagram or facebook at all. It is the browser within the app that is giving me trouble as well. No data restrictions or anything. 

Everything works fine on wifi but not on data.

If the phone can access data on normal link, Koodo data link was working. If you had certain issue with apps, there was something else with phone settings. In these cases, the most common advice is to reset the phone network settings to see if that can help.

Another way to test if the issue was from the SIM is to put the SIM into another device or use another SIM in your phone and test.

Anyway, which phone are you using? and are you a postpaid or prepaid customer?

Go into your data settings in your phone. Did you happen to turn off data use for specific apps?