There are two main ways to perform data type conversions in Power Query:

1. Using the User Interface:

This is the most user-friendly option, especially for beginners.

* Select the Column: Click on the column header you want to convert.
* Change Type Menu: Go to the "Transform" tab in the Power Query Editor ribbon.
* Conversion Options: Click on "Change Type". Here you'll see various data type options like "Text", "Number", "Date", etc.
* Additional Control (Optional): For some data types, you can choose "Using Locale" to specify how Power Query interprets text values based on regional settings (e.g., interpreting "1.23" as a number with a decimal point).

2. Using M Functions (for more advanced control):

Power Query offers various M functions for specific data type conversions. Here are some common examples:

* Text to Number: `Number.FromText(Value)` - Converts a text value (e.g., "123") to a number.
* Number to Text: `Text.From(Value)` - Converts a number (e.g., 123) to text.
* Date/Time Functions: Functions like `Date.FromText` or `Time.FromText` convert text strings representing dates or times to their respective data types.

Here's how to use M functions for conversion:

* In the formula bar of the desired column, enter the M function with the value you want to convert.
* For example, to convert a "Text" column named "SalesAmount" to numbers, you can enter: `Number.FromText([SalesAmount])`.

Additional Tips:

* Error Handling: Be mindful that data conversions might not always be successful, especially if the text values have inconsistencies. Consider using error handling functions in your M code to address potential issues.
* Data Preview: Always preview your data after a conversion to ensure the values were transformed as expected.


Remember, the best approach depends on your comfort level and the complexity of the conversion. The user interface offers a quick and easy way for basic conversions, while M functions provide more control and flexibility for advanced users.