cannot install “cmake” – E: Unable to locate package cmake

(my first question here)I tried to run the following commands (wsl for clion toolchains…):
sudo apt-get update
sudo apt install build-essential cmake gdb valgrind

It is fails in the second command. I have attached the picture of the problem (I have checked
the connection):
enter image description here

the problem:
sudo apt install build-essential cmake gdb valgrind
Reading package lists… Done
Building dependency tree… Done
Reading state information… Done

No apt package "cmake", but there is a snap with that name.
Try "snap install cmake"

No apt package "valgrind", but there is a snap with that name.
Try "snap install valgrind"

E: Unable to locate package build-essential
E: Unable to locate package cmake
E: Unable to locate package gdb
E: Unable to locate package valgrind

and after that:

sudo snap install cmake
error: cannot install "cmake": persistent network error: Post
"https://api.snapcraft.io/v2/snaps/refresh": dial tcp: lookup api.snapcraft.io on
8.8.4.4:53: dial udp 8.8.4.4:53: connect: network is unreachable

This is the sources list: enter image description here

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