How can I block pornography from being viewed on my computer?

I need something like a parental filter or something. I’ve tried going to ‘Internet Options’ >> ‘Content’ >> ‘Content Advisor’; but that blocks absolutely EVERYTHING. It says, “This page has been rated by a rating system that you do not have installed. For more information about these ratings, connect to
cz – 1
lz – 1”
I don’t want everything blocked, just pornography. I’ve gone through each item and setting the content levels to ‘unrestricted’ except for the nudity and sexual content items, but it still blocks everything. I don’t know the actual URL’s of each porn site, I just want a generic porn filter. Any suggestions? Thanks for your help.

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