List each goal once on the Goals tab — what it's for, the amount you need and the date you want it by. Every time you set money aside, add a line on the Contributions tab. How much you've saved, what's left, your progress bar and the monthly amount to hit the date all work themselves out.
The Dashboard shows your total saved, your target, what's still to save and your overall progress across every goal. Set today's date and the monthly-needed figure stays honest — if a target date passes and the goal isn't met, it shows the full amount still owed. Yellow cells for typing; the rest is locked. Opens in Excel or Google Sheets.