Zabbix monitoring API and BD

I have never used Zabbix, I just figured out how to install it on ubuntu 18.04

I have a project: .net core 2.2 (API), reactJS (UI) and postgreSQL (DB) Advise how to configure zabbix-agent for the API correctly, to Check if login page gives "200" response;

Also send a request to the database to check the connection to the database.

If the login page returns 4 ** or 5 ** and if there is no connection to the database, notify Zabbix admin by mail

Advise me maybe there are ready-made or similar solutions to this problem

Thank you for your attention, have a nice day.