YouTube has some great math videos. Those produced by Numberphile are excellent and ditto for those by Mathologer.
Here is one by Cat Sole, showing infinity might be bigger than what you thought.
And another by Cat Sole, this time showing infinity might be smaller than what you thought.
Cat Sole’s next video asks who was the greatest mathematician/scientist of all time: Einstein or Newton?
Although some would say neither, because that accolade belongs to Archimedes.