Google Drive has a few hidden tricks. Some of them I use without knowing too much who told me or where I read it. And one of them is to allow copies of a form without anyone being able to edit our original form.
Just open the document and copy its address. For example:
The link that forces the copy is built by changing the end of the address. You must replace /edit by /copy.
Of course, in order for it to work, we have to share the document with a reading permission for anyone who has the link.
And, just that, it is what makes it difficult to do so with forms. A form does not have read permission. When you create a form, you do not have to share it with reading. A form is always shared with everyone who has the link, and can not be avoided (maximum can be restricted to users of the domain if used in a G SUite for Education environment).
A first test would be to do the same procedure as in docs. Replace the final for /copy. But that does not work, it shows the screen that indicates that we do not have permissions
What is the solution then? First you have to create a shared folder in read only mode for anyone who has the link.
Then move the form to this folder (this is how we give the form an additional reading permit).
Finally, we open the form and copy its address. Now, if we change the end of the address /edit to /copy, everyone who follows the link will have the opportunity to make a copy of the form and edit the copy. Instead, he/she will not be able to change our original form (at most he/she will be able to respond).
The link will look like the following: