my ipad not turning on says suport,apple.restore

Your iPad has gone into restore mode.

You will need a Mac or Windows PC to do the restore. No other options.

If you have access to a full computer, like a Mac or Windows PC, try either using the Finder on a Mac that has the newest macOS Catalina installed OR with an older Mac with an older Mac OS, download and install the latest iTunes version ( or latest iTunes for Windows PC ), make sure the Mac or Windows PC is connected to the Internet, connect your iPad by the USB charge cable to the computer and let the iTunes application and follow the iTunes procedures that follow to do the restore.

Make sure your iPad is, at least, charged to 50% or greater to attempt this.

If NO access to a Mac or Windows computer, you will have to seek help from a good friend or family member to help you out

OR

Search online to locate and call contact your nearest, “local” Apple Store location to try/attempt to make an appointment to get your Apple iPad upgraded/updated to its latest iPadOS 14.6.

Apple Store employees will be glad to help/assist you.

You need to be aware that once an Apple iOS device goes into Restore mode, all data on that device is, effectively, lost/gone forever.

So, if you never made any device/data backups of that iPad, then sorry, all your data on that iPad is gone forever.

Sorry & Best of Luck to You!