Well the home page of the website could be small, with your topic and a few clickable subsections of your topic below it.
When you click on this sections, it could take you to knew, scrollable pages with pictures, headings, subheadings, info.
At the top of each page (home and scrollable) you could put a message that doesn’t go away, like “help with world hunger, donate to a charity today” or something like that. Make sure to put some red on it, maybe with a white background to the header. Red will make it stand out.
I wouldn’t go with a bright color scheme, since your topic isn’t a very fun thing. Think navy blue, white, black, grey. Neutral tones like that.
Don’t try to put everything on one page.
Hope this helps!