CPanel Hosting | Low Cost CPanel Web Hosting Japan

You can grant the root user access to a cPanel account with the access a cPanel user account option from WHM’s Tweak setting Interface.
(Home >> Server Configuration >> Tweak Setting)
This settings grants the root user access to a cPanel account by default.

I believe that you've already logged in to cPanel, let's learn how to change the cPanel password.

STEPS:

Click the Change Password icon.

First enter your old or existing password.

Then enter and confirm a new password.

Click Change your password now.

To manage multiple domains with one cPanel account, you can use addon domains. Below are the points to remember while managing multiple domains.
Your account must have a main domain.
You can add more domains with cPanel's Addon Domains interface (Home >> Domains >> Addon Domains).
Add the domains outside of your public_html directory in order to keep track of them easily.

https://www.scopehosts.com/secure/knowledgebase/274/How-to-create-Cron-Job-in-cPanel.html
you can refer this knowledgebase

While we create a new account in cPanel, you may find following default files and folders:

public_html: To make your website publicly available over the Internet, please upload your web pages and images into this folder.

public_html/cgi-bin: CGI Bin directory.

public_html/images: It is used to store the images for any webpages you upload.

public_ftp: It contains files to be accessible via anonymous FTP.

public_ftp/incoming Files: Files uploaded via anonymous FTP.

.cpaddons: Stores information about cPanel Add-ons for particular account.

.trash: Items deleted or moved to trash in cPanel File Manager.

public_html/.htaccess: The main .htaccess file for the pages served on this cPanel account over HTTP.

mail/: It stores the mail data.

mail/new: Stores incoming mail that has not yet been marked as received by IMAP.

mail/cur: Mail sitting on the server.

mail/tmp: Temporary directory for mail.

tmp/: Temporary files created by cPanel in various activities. Third party scripts may also use this directory for their own temporary files.

tmp/analog: Temporary files for generation of Analog stats for your website.

tmp/awstats: Temporary and configuration files for generation of AWStats for your website.

tmp/awstats/awstats.yourdomain.com.conf: Configuration file for generation of AWStats for a website.

tmp/cpbandwidth: Temporary directory for tracking bandwidth usage through cPanel.

tmp/cpbandwidth/yourdomain.com-bytes_log: Number of bytes tranferred by yourdomain.com.

tmp/webalizer: Temporary files for generation of Webalizer HTTP stats for your website.

etc: Stores other information related to your website.

Mostly .(dot) files are configuration files for the respective service. e.g., .softaculous, .fantasticodata.