That is the first thing any database tutorial would normally do;
show how to render the table data in a grid.
Follow along the previous question,
Display data form sql db onto datagridview with labled columns[
^] , and start with the "Related Questions", in the right side of this question as well. There are several other questions that answer the same thing.
This quick article might also help you,
Walkthrough: Display Data from a SQL Server Database in a DataGrid Control | Microsoft Docs[
^]
Edit
Provided the code that you have tried, as well as the comment that you made. You want to make sure that the record exists, for the data grid view and only render the records it there are any.
In that case, query is correct and will most likely fetch the data if the column names and the table and connection is correct, also the code is exposed to SQL Injection. I just wrote an answer here,
Sql injection attacks possible using resource(.resx) file[
^] , your code will most likely.
The code for the block of
reader.Read()
is already shared several times in the articles and the links I have shared in my answer above.