Making a zoom like software

Hello , I'm a 4th year computer engineering student , for our graduation project my friend and I are planning on making a software kind of like zoom , but giving it more features and stuff.

i have no prior experience in making a full software like this so I'm lost on where to start.

so i wanted to ask , for such a project where do i start exactly ?, what courses should i take , or what languages are best for it ? that i should learn in preparation for it ?