What do you mean exactly? You mean a service like Kickstarter or Gofundme, but then something that pays out in Bitcoin?
This is a crowdfunding website for charity:
https://bithope.org/Bitbay is another one:
https://bitbay.net/en/crowdfundingBitspot.me is also for personal fundraisers:
https://www.bitspot.me/There are many more, but you can find them yourself with Google. Search for 'crypto crowdfunding' or something similar.