When somebody fills out your Google Form, the answers can be saved into a spreadsheet by themselves. You only have to set this up once.
Do these three steps
1
Open your form and click "Responses"
"Responses" is the tab at the top of the form, in the middle, next to "Questions".
2
Click the small green spreadsheet picture
It sits at the top of the Responses page, on the right side. A small menu will open.
3
Choose "Create a new spreadsheet" and click "Create"
That's it. The spreadsheet opens on your screen.
You're finished
From now on, every answer that comes in is added to the bottom of that spreadsheet automatically. You don't have to do anything else.
How to look at the answers later
Go back to your form, click "Responses", and click the green spreadsheet picture again. This time it says View in Sheets. Click it, and your spreadsheet opens with all the answers in it.
If something goes wrong
The answers aren't showing up in the spreadsheet. Wait a minute and refresh the page. New answers are added one at a time, as people send them.
You made two spreadsheets by accident. Keep the last one you made — that's the one the form sends new answers to. If the older one already has answers in it, copy them across or ask me and I'll do it.
You can't find the green picture. Make sure you're on the "Responses" tab and not the "Questions" tab.