Drupal 8.x

I apologize if this is an incorrect approach. I have been using Drupal here and there for a number of years, pretty new to the forum...

Hi! I have a module that displays extra information on the user profile view. If I want to make this display element available to Layout Builder, so that the site can change where it is displayed, how would I do that? Is there documentation somewhere?

Right now, the code is:

I'm running four drupal 8.8.x sites on Bluehost and for the most part they run okay.  They're not big by web standards.  My main problem now, and I've add four separate tech chats with them about this, is enabling opcache.  They insist that it is installed by default.  It is, up to php 5.6 but the module cannot be found in in any php 7.x. configurations.  Other than switching to another provider, I guess I'm stuck with this.

I am new to Drupal. I have a working webapp in PHP/MySQL which I am trying to port to Drupal. Here is my problem:

In the webapp, I have a table called Patients with a DoB (Date of Birth) field. The input form takes in information as "Age" in years and months, and inputs an approximate DoB by subtracting from current date (This is because most of the patients, where this is used, are not aware of their DoB).

I install drupal 8 on a RHEL 7.7 VM.  After the installation, I go through the process of connecting the server to a mySQL 5.7 database.  After entering the credentials and arriving on the last page to configure the site, when I close the page and attempt to access the sever again from a web browser, I get this error, "The website encountered an unexpected error.