After re-reading your subject line, perhaps this is what you are looking for. If not, please read my original response, shown below.
Here are 2 syntax options to use the value in SHEET!A2 as the Row number for a Range reference.
With a 4 in SHEET!A2, this code will put the text shown in C4 and D4
Sheets(1).Range("C" & Sheet1.Range("A2")) = "MyText in C4"
Sheets(1).Cells(Sheet1.Range("A2"), 4) = "MyText in D4"
Please note that there is no error checking shown, so if your MATCH function does not return a valid number, the code will fail.
I would suggest using a Data Validation drop down based on the column you are searching to ensure that you will only be able to choose a name that will be found via the MATCH function. If you don't, you should include some error handling in the macro.
If you are using a macro, please post it so that we know what you are working with.
I don't understand how having the row number in A2 is used to help you "change the marks in the 4th row". How are you actually changing the marks?
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