can you please block the paid apps on my phone.
No, we can't, we are also users of Apple products & services like you.
Don't download paid apps, and be careful yourself if an app has 'In-App Purchases' with a subscription.
A free subscription does not remain free, it will be automatically converted to a paid subscription after xx time, if you do not take action in time. You should look at the conditions of the subscription, check with the app developer.
See the following Apple articles:
View your purchase history for the App Store, iTunes Store, and other Apple media services
View your purchase history for the App Store, iTunes Store, and other Apple media services - Apple Support
How apps, content, and subscriptions from Apple are billed
How apps, content, and subscriptions from Apple are billed - Apple Support
If you see "apple.com/bill" on your billing statement
If you see "apple.com/bill" on your billing statement – Apple Support (UK)
If you want to cancel a subscription from Apple
If you want to cancel a subscription from Apple - Apple Support
If the subscription that you want to cancel is not listed
If the subscription that you want to cancel is not listed – Apple Support (UK)
Click here for more support and assistance.