How do I completely renew an APP from my phone during the "trial period" if I have no intention of ever using the APP in the future

Cancel the subscription as described in my previous post.

Then delete the app -- see the following:

If the app is on a Home screen, touch and hold the app, tap Remove app and then tap Delete App (or tap Edit Home Screen in the pop up menu, tap the minus sign, then tap Delete App)

If the app is only in the App Library screen (swipe left past the last Home screen), touch and hold the app there and then tap Delete app.

Note that some built-in Apple apps cannot be deleted.

If neither of those options is available, there may be a restriction set on deleting apps. On an iPhone or iPad, go to Settings > Screen Time > Content & Privacy Restrictions > iTunes & App Store Purchases > Deleting Apps.

See: https://support.apple.com/en-us/HT201304#prevent-purchases

Also be aware that deleting an app does not cancel any related subscriptions. To do that, see: https://support.apple.com/en-us/HT202039

Cancel the subscription the same way you would a paid subscription: How to cancel a subscription from Apple - Apple Support