Not working at all

[EtienneDelepine]

Hi,
I'm already using the old v1.8 and wanted to install the latest v2.0 on the same server. This is a linux (oct 2022) + Apache 2.4 + MySQL 5.7
Following the installation guide, the files and database were well deployed. I had the first screen to configure the database credentials but once saved, the app starts looping indefinitely from signup to logout (screenshot joined).
The file database.php was well updated with the good credentials.
The file /tmp/error.log contains dozens of errors (file joined) just by doing that.

I started going from errors to errors and each time a bunch of new PHP errors comes!
I downgraded PHP from 7.4 to 7.2 (not maintained anymore) but still have hundreds of errors (undefined constants and variables, even missing .ctp files, and worse...)
I tried on my local Windows but same thing.

I finally was able to create a user but with missing data in the database (company then company_users, user_subscription...) due to process stopped by PHP errors.
At the end of this hard work, /users/manage displays with lot of errors and /dashboard sends a 304 empty page.

What happen to this app? How can I just update from 1.8 to 2.0 on the same server without debugging hundreds of code errors?
Thank you for help.

error.log