Problems with Safari

Witam.

Try basic troubleshooting option:

Try to reset your device. This won't delete your data stored on this device.

• Press and hold the Sleep/Wake button
• Press and hold on the Home button
• Keep holding both buttons until the display turns off and back on with Apple logo on it.

You may try to check the restrictions settings. Some options in restrictions may be enabled. Probably "Limit adult content" option.

You may also have private browsing option enabled(you visit sites but it leaves no history) Try to disable it.

Safari web settings on your iPhone, iPad, or iPod touch - Apple Support

Milego dnia.

I think you do have some restrictions for websites enabled. Go to Settings>General>Restrictions>Allowed Content>Websites>All. See if that allows you to clear history and website data again.