set_system_wide_proxy

https://computingforgeeks.com/how-to-set-system-wide-proxy-on-ubuntu-debian/

Set System-Wide Proxy settings on CLI
We will add a shell script file under /etc/profile.d/proxy.sh. This will ensure the settings apply to all logged-in users.

sudo vim /etc/profile.d/proxy.sh
Populate your proxy values.

# set proxy config via profie.d - should apply for all users
# 
export http_proxy="http://127.0.0.1:10809/"
export https_proxy="http://127.0.0.1:10809/"
export no_proxy="127.0.0.1,localhost"

# For curl
export HTTP_PROXY="http://127.0.0.1:10809/"
export HTTPS_PROXY="http://127.0.0.1:10809/"
export NO_PROXY="127.0.0.1,localhost"

Add other IPs you want to exclude from proxy to NO_PROXY & no_proxy environment variable.

Make it executable.

sudo chmod +x  /etc/profile.d/proxy.sh
Source the file to start using the proxy settings, or alternatively logout and back in.

source /etc/profile.d/proxy.sh
Confirm:

$ env | grep -i proxy