Every time you complete one of those Captcha puzzles you train the robots. They will soon become obsolete, for that reason.
Whatever malware you installed, uninstall it. Yes that is, was, and will always be a waste of time.
If you can't get past one of those challenges, it is possible the website demanding it is malfunctioning, including the server it contacts to send the Captcha puzzle and reply to the website with its conclusions you either are or are not sufficiently human.
Try each one of the recommendations in If Safari isn't loading websites or quits on your iPhone, iPad, or iPod touch - Apple Support.
Add to them: if you're using a VPN, don't.