How to inspect and validate a deb package before installation?

I want to give a GUI based desktop user friendly solution. I am using Ubuntu Mate 18.04

Double click the .deb file. It Will open in Gdebi.

If it is not already installed you can install Gdebi using sudo apt-get install gdebi.

When you Double click the .deb file, you can find the Package Name, Dependencies, Which Files it will install and where and much more.

If you decide to install the package use Install Package

https://askubuntu.com/questions/642665/how-to-inspect-and-validate-a-deb-package-before-installation