You can use an IR pass filter on a normal webcam to only allow IR light, but for better quality and ease, a dedicated IR camera is preferable. Yo can see here https://oldrollpro.com/
Yes, of course: UV photography is used in forensics and 'bee view' flower photography, for example. Humans are trichromates and so are bees. But they see UV and do not see red. Some flowers look totally different to bees than to us.
For the fun part: It would not be a problem to make a camera to see if sunbathing people use an efficient sun blocker and if they applied it to the whole skin or if some parts are missing.
You can use an IR pass filter on a normal webcam to only allow IR light, but for better quality and ease, a dedicated IR camera is preferable. Yo can see here https://oldrollpro.com/