Problem whit signal app install

Hi everyone, I just joined the forum because I have a problem !!!
I tried to install signal without success and now I am getting these errors.
E: Type ‘sudo’ is not known on line 2 in source list /etc/apt/sources.list.d/signal-xenial.list
E: The list of sources could not be read.
E: _cache->open() failed, please report.
Could you please help me?
Thanks.

DISTRIB_RELEASE=4.10

This might help.

sudo dpkg --configure -a

sudo rm /etc/apt/sources.list.d/signal-xenial.list

NOTE: These instructions only work for 64 bit Debian-based
Linux distributions such as Ubuntu, Mint etc.

# 1. Install our official public software signing key
    wget -O- https://updates.signal.org/desktop/apt/keys.asc | sudo apt-key add -

# 2. Add our repository to your list of repositories
    echo "deb [arch=amd64] https://updates.signal.org/desktop/apt xenial main" | sudo tee -a /etc/apt/sources.list.d/signal-xenial.list

# 3. Update your package database and install signal
    sudo apt update && sudo apt install signal-desktop