Error install Centos 8

Hi Guys

I did the installation procedure through the website itself, following the step by step. I use thecentos 8 version with apache. After finishing the installation, I tried to open the url

I got the error below

when running ./validate, I saw that I couldn’t connect with the database and I managed to correct it by putting the necessary information inside the .env file.
Still, I couldn’t start the installation process. I also checked SELINUX and it is permissive.
I saw that there are some manuals that ask for the use of install.php, but this file does not exist.
I do not know what else to do.