Hi Gagan,
Thank you for reaching out. Please find my response to your questions below:
We recommend you use the official Adwords API/Google Ads API to build your app or integrate to your existing app. These official APIs provide many useful functionalities with detailed documentation and helpful examples. You would be able to implement it with the help of these resources.
The majority of developers would prefer using our official APIs. If you consider it too complex, you could always divide it into subproblems and solve it one by one. Use the information provided on the API Documentation and also keep in mind that we are ready to help you out with any issue you have encountered.
Thanks and regards,
Xiaoming, Google Ads API Team