Before you begin, thoroughly read and understand the API documentation. Identify the endpoints you need, the data formats, authentication methods (if any), and any rate limits or restrictions. This will help you plan the data extraction process effectively.

Install the necessary tools and libraries required for the task. You will typically need a programming language such as Python, Node.js, or JavaScript, along with libraries for making HTTP requests. For Python, you might use `requests`, and for Node.js, you might use `axios` or `node-fetch`. Ensure MongoDB is installed and running on your system or accessible through a cloud service.

Write a script to make HTTP requests to the API endpoint. Use the library of your choice to handle the request and retrieve data. Handle any authentication required by the API, and ensure you respect the rate limits by implementing proper error handling and retries if necessary.

Once you have the data, inspect and transform it as needed. This might involve converting data types, renaming fields, or filtering out unnecessary data. Use data manipulation libraries such as `pandas` in Python or native JavaScript methods to prepare the data for insertion into MongoDB.

Use a MongoDB client library to connect to your MongoDB instance. For Python, you might use `pymongo`, and for Node.js, the `mongodb` driver. Ensure you have the necessary credentials and connection string to access your MongoDB database.

Once connected, write a function to insert the data into your MongoDB database. Choose between inserting data as a single batch or one document at a time, depending on the size of your dataset and performance considerations. Make sure to handle any errors, such as duplicate keys or validation errors, during the insertion process.

To ensure the data in MongoDB stays up-to-date, automate the extraction and insertion process. You could use a simple cron job on Unix-based systems or Task Scheduler on Windows to run your script at regular intervals. Ensure your script logs its activity and any errors for monitoring and troubleshooting purposes.
By following these steps, you can efficiently transfer data from a public API to a MongoDB destination without relying on third-party connectors or integrations.