Requirement: How to add 365 days to the given date using Power Automate.
In Power Automate, Click on +create from Home Page , select instant flow, Provide name to the flow, select manually trigger a flow , then click on Create Button, then click on the Next step.

Power Automate add 365 days to date
Next, initialize a variable to sore the date, so click on the Next step and select Initialize variable action. Then provide the variable name, type as string, and in value add a date.

How Power Automate add 365 days to date
Next, add 365 days to the above date, so click on the Next step and select compose action. Then in Input provide the below expression:
addDays(variables(' Date'),365,'yyyy-MM-dd')

Microsoft Flow add 365 days to date
Now click on Save and run the Flow, to see the 365 days are added to the given date.

MS flow add 365 days to date