In the world of internet, it is not a good idea to build all functionalities in your product when we have others providing the functionality for you to integrate into your website for free or at minimal cost.
It is best to focus on your core idea and let others handle what they are good in.
Many platforms provide API (Application Programming Interface) to let people use their services from other website/product. Few of them are open source (you just need to create an account to use) and few are paid.
We at Gaurish technologies are the expert using open source APIs and Paid APIs and have implemented many in the past and keep on doing the same for our valuable customers.
Below is a list of few we have implemented so far in different projects.