Hi Chs,
I configured a flow to send an email when the Date column in the list is less than or equal to Today. My flow configuration looks like below:

Then when an item is created, if the data is less than or equal to Today, an email would be sent.
In the SharePoint list, the Date column is Date only format. What’s your data source? If you are also using SharePoint list, please make sure to configure the Date/Time column as Date only format.
Please try to configure the Condition with the formula as following:
@lessOrEquals(triggerBody()?['Date'], formatDateTime(utcnow(),'yyyy-MM-dd'))
The workflow definition contains the actual logic that executes as a part of your logic app. This includes one or more triggers that initiate the logic app, and one or more actions for the logic app to take. Hope this documentation about Workflow Definition Language could be a reference for you:
https://docs.microsoft.com/en-us/rest/api/logic/definition-language
Please try it on your side and let me know if it works for you.
Best regards,
Mabel Mao