Hi @Steve-GEDS, Welcome to Lightroom Forums! Your Lightroom mobile subscription purchased through the App Store on your iPhone will also work on your iPad if both devices are signed in with the same Apple ID and you're using the same Adobe ID within the Lightroom app.
When you install Lightroom on your iPad, it may prompt you to download a version optimized for iPad, which is normal. This version is still part of the same Lightroom mobile app family and will recognize your existing subscription. Lightroom on mobile is designed to work seamlessly across the entire Lightroom ecosystem. If you're using Lightroom on your tablet, you can also access any edits you make in the mobile app. Here is some more information about your subscription: https://www.adobe.com/products/photoshop-lightroom/mobile.html
I hope this helps! ^CH