upgrading browser for Mac OS 8.7

A friend has a Mac Powerbook G3 with 8.7 installed.

He also has a Mac desk computer but doesn't know too much about the
internals.  I know less.

For the Powerbook, I think his browser won't handle a lot of webpages
with newer html code.

Is there an inexpensive way to upgrade the browser?

Or to upgrade the OS and then the browser?

Thanks.

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for some reason, remove NOPSAM  :-)