I am currently working with IBMi. I want an automatic mail after completing few jobs for confirmation. How can I achieve this? I can run Python in my system.
IBM has built in commands depending on your OS release.  They do require setting up the IBM SMTP server.  SNDSMTPEMM and SNDDST are the most used.
There are also third party products like my MAILTOOL software (www.bvstools.com/mailtool.html) that makes interacting with cloud servers like Office 365 and Gmail much easier than then IBM SMTP server.
PHP may also have some built in email capabilities as well as python.  But if you're looking for a command line interface after running jobs the first two are probably your best bet, depending on if you want to set up the IBM SMTP server or not.
How to automate mail in IBM i system