Update table using datagridview in VB.NET and mysql

Hello Everyone Good Afternoon.

I have a table in MySQL and I used to Show it using Datagridview and this is what it looks like

Item Name       Qty
Apple            0
Mango            0

I will click Export button and what happens next is that the Data in Datagridview will Extract into an excel sheet same as the Illustration above.
I will edit the Extracted Excel Data and I will put anything I want but for now here is the Example I will do.

Item Name    Qty
Apple         100
Mango         100

I will click the Import Button and the excel will overwrite the Data in Datagridview.
My question here is that How can I update the changes happened in datagridview in Mysql Database using the RefID in Textbox1?

I hope you all get It, Im Using VB.Net and Mysql

TY