This is a common question with many answers on the internet. A simple Google search will give you many solutions:
winform datagridview cell background color - Google Search[
^]. Also there are related questions with solutions to the right of this one.
Here is an example of one Question with a Solution from here on Code Project:
Change background color of cells in DataGridView C#[
^].
Lastly, in a previous solution to one of your many other questions, I showed you how to use ChatGPT to convert C# to VB. So if you find a C# solution that you want to use, you know how to convert the code.