How to use OAuth 2.0

I have written JIRA api in postman to create JIRA tasks using Basic Authentication.
Now I am trying to do the same thing using OAuth 2.0
I was going through the learning docs present online for understanding rest api but not able do it practically.

Basically my requirement is Creating JIRA tickets via rest API using OAuth 2.0

The link above might be of some use. It might be a little convoluted though.

The following Q/A might be of some use as well