The attempt to load websites failing.

Hello. So, I bought a old Powermac G4 a couple days ago, and I started it up today, and I have been trying to go to the internet using internet explorer which i presume the old owners installed. But when I try and go on some websites, for this example i will used one called "perpheads.com" (which i used daily on my windows 10 pc) I get the error "The attempt to load 'Accessing URL: http://perpheads.com/' failed." Please help as this is happening on most websites and I don't know what to do.

The computer info that I know:

Operating System: Mac OS X Version 10.0.3 (Build 4P13)

Memory: 256 MB

Processor: PowerPC G4

If there is any more information you need just tell me how to get it (Im an advanced Windows user but i am new to Mac.)