How can I design a Flow in Power Automate to capture the previous values of updated CRM data? Is there a method to access and retrieve the old data before it was modified, like the use of preImage?
Power Automate is asynchronous so you don't have a PreImage like you have in Plugins.
One alternative approach is to enable auditing and retrieve the audit history values, this method is described here
https://azaanzaki.blogspot.com/2024/10/how-to-retrieve-pre-image-data-using.html