One of the first things to consider is what kind of data you have to work with in your cash flow template Excel spreadsheet. Ideally, you're looking for accurate monthly data including income statement items like revenue and operating expenses and balance sheet items like equipment purchases and cash from financing activities. If you have a longer time frame you can go with quarterly periods, but annual tends to be too long. After all, how can you predict what is going to happen beyond 5 years with any accuracy unless you're valuing an annuity?
Alternately, you may select an entire row by moving your mouse to the left_most cell in a row. When the cursor changes to an arrow, click the mouse and the entire row will be selected. You may select an entire column by moving your mouse to the top_most cell in a column. When the mouse pointer changes to an arrow, click the column and all cells in it will be selected. Once the desired cells have been selected, you may apply formatting changes to your selections as desired.