Date is changing issue while Dynamics crm to Power bi

Hello Gopal_PV,
First thing to look at is how the EffectiveDate column is set up in Dataverse. If it's already showing the wrong date before Power Query even touches it, I will start by checking the column configuration in Dataverse.
Is it one of these?
Date Only
Date and Time (User Local)
Date and Time (Time Zone Independent)
Asking because User Local columns get stored as UTC and then converted on retrieval, the other two don't do that conversion at all, so it makes a real difference which one you've got. Date Only and Time Zone Independent don't go through that conversion, so the column behavior could explain the one-day shift.
Also curious:
Does this happen for every record or just this opportunity?
What's the data type of the EffectiveDate column?

Microsoft has a good explanation of the different date/time behaviors:
Configure the behavior and format of the date and time column by using code 

Once we know the column behavior, it'll be easier to tell whether this is coming from the Dataverse configuration or something specific to the connector.