"Upstream" where can I see the load?

Debian GNU/Linux 10 x86_64(Py3.7.9)　

For some reason I have a lot of output traffic. How can you see who is eating so much traffic?
Is there a simple option? I don't really understand.

Toyota
Hello, try to use the iftop command to view
apt install iftop -y && /sbin/iftop