I'm making a website that displays a feature for the user to donate/ volunteer, but I don't have a clear idea on how to go around and embed it, I want the user to actually have their money sent to real donation associations or if they choose volunteering then their information sent to a volunteer related associations, do I contact those said association to get a section of their website code and embed it into mine? I want my website to be like a mediator between the user and the association, that's my idea on how to implement such feature.
I'd really appreciate any help or sources to read about how to do such tasks.
I did some research and they weren't helpful, I want the donation or volunteering to be related to a specific cause, so the receiving end of these features are specific organizations and not just a Paypal donation section, and I couldn't find enough information for this type of requirement.