I tried to install LimeSurvey locally in Ubuntu 18.04 and strictly followed the instructions given at: websiteforstudents.com/install-limesurve...mariadb-and-php-7-2/

At https://localhost/ I get the Apache2 Ubuntu Default Page.
At https://localhost/phpinfo.php I get the PHP default test page


Instead of:
wget download.limesurvey.org/latest-stable-re...3.14.3+180809.tar.gz
tar -xvzf limesurvey3.14.3+180809.tar.gz

I ran:
wget download.limesurvey.org/lts-releases/lim....22.20+200617.tar.gz
tar -xvzf limesurvey3.22.20+200617.tar.gz


After having enabled the LimeSurvey Site and Rewrite Module, the LimeSurvey installation page should be found at:

example.com/

But this does not happen, I got a website with the message:


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Example Domain

This domain is for use in illustrative examples in documents. You may use this domain in literature without prior coordination or asking for permission.

More information...
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Can you tell why the installation page does not show up?

In which folder were you when you ran
In the provided link there is this line of code:
Did you follow this? If so, Limesurvey is installed into the subfolder "limesurvey".

So to access Limesurvey it would be example.com/limesurvey/

Depending on how you unpacked it, it might be actually within another folder within this /limesurvey/ folder.

Look at your folder structure.

Or you made a mistake here:
This is where the tutorial configures the Domain example.com to the folder "/var/www/html/limesurvey" on your server.

And I hope you don't actually use "example.com", but rather your domain, right? (you never know...)

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Example Domain

This domain is for use in illustrative examples in documents. You may use this domain in literature without prior coordination or asking for permission.

More information...
---

Just looked at example.com and YOU DID use Example.com!!!!!

Of course you can't use example.com, it is not your domain. This is just a placeholder for your own domain. You need to purchase a domain and redirect it to your server.

Thanks, you brought me on the right track.
I am running LimeSurvey locally, so the site was found at:
https://localhost/limesurvey/