HI @RH-MP
Currently a trigger based on a change of a particular field of a sharepoint list item is not supported in flow. You can submit an idea here:
https://powerusers.microsoft.com/t5/Flow-Ideas/idb-p/FlowIdeas
Alternatively, as a workaround, you have mentioned the field is set to No by default so you can use the trigger when an item is created or modified and after the trigger, place a condtion to check if this field is yes and then run the flow else terminate.
Hope this helps!!
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