Hi.
You can resize columns as you would normally in excel if you click the black FULL SCREEN button on the top right to display the column lettering. Just drag the edge of the column lettering box to the left or right to resize.
You will notice some columns have an 'h' above them. If you click the beige colored Hide 'h' Columns button, it will toggle between hiding those columns and displaying them. You can add or remove an 'h' from any columns that you choose and then toggle between hiding them and displaying them with that button.