Financial Planning is a two-step exercise.
Step 1: Enumerate your income sources and contrast this tally with your expense total. You can work from monthly or annual depending on your situation. Make sure to include those pesky “one-offs” like car repairs, school activities or holidays. Include everything.
Step 2: Inventory all of your assets that will be used or can be potentially used as retirement funds sources such your RRSP, real estate holdings or other investments. You will then want to identify your current as well as future liabilities. These could include your mortgage or future caregiving expenses for a loved one that you expect to be responsible for.
The outcome of this two-step exercise is a tally of your future expenses and expressed a function of your available assets to fund these (as in the sources of the future cash flows). The answer is binary; you either have enough assets vs your expense, or you do not.