Select the cell below the rows and to the right of the columns you want to keep visible
Go to the View tab
Click Freeze Panes
Choose Freeze Panes
To freeze the top row, go to View, click Freeze Panes, then choose Freeze Top Row
To freeze the first column, go to View, click Freeze Panes, then choose Freeze First Column
To unfreeze cells, go to View, click Freeze Panes, then choose Unfreeze Panes