Error Downloading and Accessing Mavproxy on Raspberrypi

Thanks in advance, I am very beginner at this and am trying for my first time to establish communication via MAVLINK from a raspberry pi 4 to a pixhawk 2.4.8

I followed all the instructions on the MAV proxy documentation here-
https://ardupilot.org/mavproxy/docs/getting_started/download_and_installation.html#mavproxy-downloadinstalllinux

1st error, when trying to install Mavproxy using pip3 there is an " error: externally-managed-environment". I worked around this by using --break-system-packages (which I know isn’t the best but it was the only workaround I could find. I mention it in case it created other errors)

2nd, when trying to execute this command: echo ‘export PATH=“$PATH:$HOME/.local/bin”’ >> ~/.bashrc

I get an error saying ~/.bashrc: no such file or directory

I’ve double checked the bashrc file exists and it does. I’ve also tried just starting mavproxy but it always says something about mavproxy not existing.

Any help would be great