I cannot find the reminders app

if you place your finger on the screen and move it downwards and type in reminders in the search field does not reveal where it's located then it may have been deleted

Delete built-in Apple apps on your iOS 12, iOS 13, or iPadOS device or Apple Watch - Apple Support

Check better all your screen pages and/or folders. The icon could have been accidentally moved to a different position.

If you're sure it's missing, it could have been accidentally deleted. Redownload Reminders app from App Store.

Regards

Giulio

Glad you could work it out.

Giulio