I need to create a Risk heat map.

Hi Manikanta2108,

I have created a sample report with heat map. Using/Referring this report you can achieve your requirement. Please follow the steps to achieve.
Step1: I hope you have data of Risk ID, Likelihood and Impact.
Step2: Create a measures for Risk Score & Risk Severity.

Risk Score = SELECTEDVALUE('Table'[Likelihood]) * SELECTEDVALUE('Table'[Impact])
Risk Severity = 
VAR Score = [Risk Score] // SELECTEDVALUE('Table'[Likelihood]) * SELECTEDVALUE('Table'[Impact])
RETURN
    SWITCH(
        TRUE(),
        Score >= 20, "Critical",
        Score >= 12, "High",
        Score >= 6, "Medium",
        Score >= 3, "Low",
        "Informational"
    )

Step3: Create a Matrix Visual

1. Visual: Matrix

2. Rows: Likelihood

3. Columns: Impact

4. Values: Count/FirstName of Risk ID

Step 5: Apply Conditional Formatting

To color cells based on the severity, do this:

1. Click the Values section in the Matrix

2. Click the dropdown → Conditional Formatting → Background color

3. Choose Rules

4. Set up rules based on Risk Score

I am also attching a .pbix file for you refreence. 

https://drive.google.com/file/d/1DiZcWDQujOa9NaU-ehzQuyiQjcc4FuHA/view?usp=sharing 

Thanks,
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