Ask HN: How complicated is it to make an E2EE messenger?

So I'm a CS student, and should start working on my capstone project this November. I'm thinking about building a chat application that has a fully implemented E2EE from scratch. I've made some research on the topic, and the principle doesn't seem too complicated. Would this be a suitable project?

I have 8 months to work on the project. The features can range from just sending text messages to sending pictures, videos, and voice notes. How feasible is this to a third year student?

Thank you.