Raspberry pie uses a ARM cpu therefore it cannot run Windows OS. It uses Raspberry Pi OS is based on debian and has Libre office package to edit & view documents and you can use the browser to access zoom (full article link). But this Raspberry platform is more suited for people who like to tinker & do stuff manually and might not be suitable if you want it to "just work".

It can run android too but it's not officially method. Yes, you can connect a touch screen. If you want a mini PC for Windows you can look for "stick PCs" or Intel NUC systems.