I need to build a system(web app) where people will share their projects and will receive funding against those projects if someone likes the projects. The backend should be secure, and the tools that will be needed to build that system should be free. We are a startup that can't invest too much in tools right now. We need to build it in 3-4 four months.
The application should be able to support 10k users for now and should be able to scale later.
Also, please suggest what front-end technologies I should use.
Depending on the backend I would pick the technology you feel most comfortable with, although, my preference would go to Django with Django REST Framework considering the timeframe you mentioned.
As for the front-end, React.JS and Vue are easy to get started with.