Is there a tutorial for updating the PHP configuration from 7.2 to 7.4 for an instance of NC 20 on Ubuntu 18.04 using the hanssonit installation method? It’s fully automated, but have tried a couple times to update and while I can install 7.4 on there, the NC install keeps trying to use 7.2. This is preventing me from updating Nextcloud to version 22. Thanks!
I am by no means a NC expert and someone may have an answer for this.
But I spent months researching this, and finally came to the conclusion that this was not possible for me to accomplish. I was unable to locate any relevant information published by anyone on this specific issue. I did try fixes based on non-hanssonit installations, but all failed for me.
I finally spent a great deal of time researching how to take a base (free version) hanssonit install and increasing the disk size. There are a few posts scattered here and there on the internet that explain how to do this. Some of this information is out-of-date and unreliable, but after much trial-and-error I did get it to work.
I then simply began using the new NC hanssonit instance. I did export everything I needed from the old instance. The import process to the new install was very messy and not fully reliable, in my opinion. But I didn’t lose any critical data, as far as I can tell.
If this were a mission-critical NC install (it is not), I would have paid hanssonit for tech support. (I did have a paid version of the 1TB hanssonit virtual image). If I recall, they discuss on their website why going from 7.2 to 7.4 is a problem with their images.
However, I have very pleased with the final result. The benefits of the new fully updated NC install were worth the time and aggravation for me. As well as being an interesting and challenging learning experience.
There is a support option in the shop:
I understand that this is a business, but there are those who do not have the opportunity to buy technical support, or hire a specialist to solve problems with upgrades, and have to do it alone, being the beginner in such things 
What should such people do?
We all started somewhere, me too. 
When I learned linux I found a lot of resources online, trial and error.
Since you have a VM you can do a snapshot before each try, and if you fail, just revert the snapshot. You’ll learn a lot along the way. 
I understand that, and that’s how I learn a lot, too. But as you said you have a lot of dependencies in the VM, and it’s need to understand and know.
I would be very grateful if you could give some advice where and what to look for, I am really zero in PHP, so it will not learn so quickly?