How can I stop spam texts?

You can block those incoming spam text numbers however these scammers will just continue to create and use other phone numbers. This is an ongoing battle between the scammers and the cellular service carriers. In the end, at present, there is no available method that you can implement to completely stop spam/scam texts. What you can do is attempt to control it by opening Settings ➡️ Messages ➡️ Filter Unknown Senders: What this will do is move all the texts from senders that are not in your contact list to another tab in the messages app. This will allow you to determine whether the texts came from known senders or not.

More information on Spam/Scam below:

All about scams and phishing -

Beware of ➔ Phishing & Other Suspicious Emails 

Know how to Identify legitimate emails from the App Store or iTunes Store 

Avoid phishing emails, fake 'virus' alerts, phony support calls, and other scams ➔  Use these tips to avoid scams and learn what to do if you think your Apple ID has been compromised.

Axel F.