Sudo apt-get update not working

Hello,

In the Terminal I want to install the freerdp to work on a project.
I paste the command sudo apt-get update in Terminal, but it is not working.
Please see the screenshots below.
Do you have any idea why is not working?
Thank you very much!

Cause it’s a flapak-based system, so search for your program at flathub.


@Elena Endless OS already comes with Flathub enabled by default just open the app center and download the applications

@LeandroStanger, unfortunately I couldn’t find the app I need on Flathub. I need to install FreeRDP because this is the app recommended to work with on this project.

Maybe this app does what you need?
https://flathub.org/apps/details/org.remmina.Remmina