Hey @ajithd6368
You can just delete the trigger of the flow. It will just delete the trigger and after that you can add whatever trigger you want. And all the actions below will come back again.
See this below:
I have 5 compose actions:

Then I will just delete the trigger:
But the below actions will still be there and then you can select a new trigger.


You can apply one more technique where you can make a copy of your flow and then make changes in the copy and rename it.

You can do this by click on three dots of the flow and clicking on save as. This will just make a copy of your flow. Then you can make changes in your copy flow and rename and change it, whatever changes you want to make.
If you have any other doubt, just reply.
I hope this helps 🙂