Greetings Paquan,
We’re going to recommend the first place you start with this is Settings > Screen Time > Content & Privacy Restrictions. Some specifics to look at in there:
• Content Restrictions > Web Search Content
• Content Restrictions > Web Content
Even if Content & Privacy Restrictions are disabled as a whole, check those specific ones to be sure they aren’t set to restrict anything.
Another thing to consider is whether there is a management profile installed on your device. That would typically be from a corporate or educational environment. Install or remove configuration profiles on iPhone
Install or remove configuration profiles on iPhone
Configuration profiles define settings for using iPhone with corporate or school networks or accounts. You might be asked to install a configuration profile that was sent to you in an email, or one that’s downloaded from a webpage. You’re asked for permission to install the profile and, when you open the file, information about what it contains is displayed. You can see the profiles you have installed in Settings > General > VPN & Device Management. If you delete a profile, all of the settings, apps, and data associated with the profile are also deleted.
Thanks.