Need consultation for lost iPad with no find my device. I want to lock it

Here is Apple’s advice for lost or stolen devices:

If your iPhone, iPad or iPod touch is lost or stolen – Apple Support

Use the Find My app to locate a lost or stolen device – Apple Support

Facilities to manage/recover a lost or stolen device are predicated on Find My iPad being enabled on the device before it was lost.

If you did not have Find My activated on the device, you can't.

Without Find My active on that iPad, there is absolutely no way to do anything remotely with that iPad to lock/deactivatr it.

Sorry.