Django is a web application development framework written in python. It allows developers to build database driven web applications. As it is written in python it's quite easy to understand and pick up and it's also quite powerful. Django was written to build the backend of news publication sites, but has since grown a lot and is now used to build and power the backend of many websites.
If you wish to learn more about Django you can take this end to end Django certification course.
If you just wish to get your feet wet and try Django out you can follow this Django tutorial.
Also, check out this professional Full Stack Developer Training, designed to enhance your skills in the field.