How to lock my lost ipad

Log on to ➔ www.icloud.com with your Apple ID and Password. Then, follow the procedure below:

Turn on Lost Mode or lock a device - (Copied from Apple Support Article)

1. In Find My iPhone on iCloud.com, click All Devices, then select the device you want to put into Lost Mode or lock.
2. If you don’t see All Devices, it’s because you’ve already selected a device. Click the name of the current device in the center of the toolbar to access the Devices list, then select a new device.
3. Click Lost Mode or Lock.
4. 
5. Follow the onscreen instructions, keeping the following in mind:

• • Passcode: If your iPhone, iPad, iPod touch, or Apple Watch has a passcode, it’s required to unlock the device. Otherwise, you’re asked to create a passcode now. If you’re locking a Mac, you must create a numerical passcode, even if you already have a password set up on your Mac. This passcode is distinct from your password and is only used when you lock your Mac with Find My iPhone.
  • Family Sharing: If you’re trying to place a family member’s iPhone, iPad, or iPod touch in Lost Mode and the device doesn’t have a passcode set, you must enter that person’s Apple ID password on this computer. If you’re trying to lock a family member’s Mac, you must enter that person’s Apple ID password on this computer.
  • Contact information: If you’re asked to enter a phone number, enter a number where you can be reached. If you’re asked to enter a message, you may want to indicate that the device is lost or how to contact you. The number and message appear on the device’s Lock screen.

Axel F.

Start here: https://support.apple.com/en-us/HT201472