Is it possible to restrict the sites that teens can contact to such as TikTok or Instagram?
First of all, I'd change your forum username, because your current one is a privacy risk and leaves you open to getting spam.
Verizon offers a perk called Verizon Family Plus, which allows you to monitor your children's web usage and block content. Depending on what type of devices your children are using, you might also be able to passcode protect access to app stores so they can't download apps.
I found this on the website regarding Verizon Family and Verizon Family Plus:
https://www.verizon.com/support/verizon-family-faqs/
