Put my Apple ID in my kids' devices and now they're receiving my texts

You should not use your own Apple ID to set up your Childs device. Instead, you will need to make an under 13's ID for them

See this instructions on how to do that

Children under 13 can't create an Apple ID on their own. (This age varies by region.) But if you're the family organizer or a guardian, you can create an Apple ID for your child.

On your iPhone, iPad, or iPod touch

To verify that you're an adult, you need a credit card. On your iPhone, you can also use a driver's license or state ID added to Wallet where available.

In iOS 16 or iPadOS 16 or later

1. Go to Settings > Family. 
2. Tap the Add Member button .

See this link for further reference Create an Apple ID for your child - Apple Support

1. Tap Create Child Account, then tap Continue.

1. Enter the child's name and birth date. Be sure to enter the correct birth date — you can't change it later.
2. Follow the onscreen instructions to finish setting up the account. For your child's Apple ID, you can use their email address, the suggested @icloud.com address, or their Game Center nickname. 

Hello Ziade,

As mentioned earlier, they are getting your information because you are sharing your ID with them and they need their own accounts (Make sure that each family member has a unique Apple ID - Apple Support). These two documents will tell you how to set up accounts for them and also special features that are available for managing children accounts:

Create an Apple ID for your child - Apple Support

Help your child set up an iPhone, iPad, or iPod touch - Apple Support