For browser history it's actually not deleted (if signed in) until you manually do so or have chosen to automatically delete the data after a set period of time (available options are 3 or 18 months). There is no 'black and white' page that states this as you want (not without actually taking some effort to read and understand other items).
The only way to see this in 'plain text' at a quick glance is to log into the My Activity section of your Google account, and under the Web & App Activity section you'll see whether the data is being kept until manually deleted or if automatically purged after 3 or 18 months.
https://myactivity.google.com/
The 'closest' you'll get to an official document stating this is this, under the 'Information Retained until you remove it' and 'Data that expires after a specific period of time', but for that you'd need to understand first that the Web history/activity falls into the first category. This from the article:
We’ll keep this data in your Google Account until you choose to remove it. And if you use our services without signing in to a Google Account, we also offer you the ability to delete some information linked to what you use to access our services, like a device, browser or app.
https://policies.google.com/technologies/retention