You can create a 'Welcome' page when creating a form. 'Welcome' page is not displayed to respondents if there is no content. Writing content for 'Welcome' displays 'Welcome' page to respondents prior to responding the form and respondents can begin responding the form by clicking 'Start' button below. You can utilize the 'Welcome' page freely for introduction to survey, survey method, etc.
The thank you page is always enabled by default. If left blank, a default message will be shown, but creators are free to enter their own custom message.
You can create multiple Thank you pages. While using multiple Thank you pages, you must set the End response logic to set which Thank you page to move to at the end of the survey. If there is no logic setting, the default Thank you page T0 is always used. (If you add Thank you pages, it is numbered like T0, T1, T2…. T stands for Thank you page.)