installing R in ubuntu 20.04

Question

I am trying to re-install R in ubuntu 20.04 when I use

 sudo apt-get update 

I get the following error

Hit:1 http://dl.google.com/linux/chrome/deb stable InRelease
Hit:2 https://cloud.r-project.org/bin/linux/ubuntu bionic-cran35/ InRelease    
Hit:3 https://cloud.r-project.org/bin/linux/ubuntu focal-cran40/ InRelease     
Hit:4 https://cloud.r-project.org/bin/linux/ubuntu xenial-cran40/ InRelease
Hit:5 https://cloud.r-project.org/bin/linux/ubuntu bionic-cran40/ InRelease
Hit:6 https://cloud.r-project.org/bin/linux/ubuntu eoan-cran35/ InRelease
Hit:7 https://deb.leap.se/client release InRelease
Ign:8 https://cloud.r-project.org/bin/linux/ubuntu bionic-cran InRelease
Ign:9 https://cloud.r-project.org/bin/linux/ubuntu focal-cran36/ InRelease
Err:10 https://cloud.r-project.org/bin/linux/ubuntu bionic-cran Release
  404  Not Found [IP: 143.204.201.112 443]
Err:11 https://cloud.r-project.org/bin/linux/ubuntu focal-cran36/ Release
  404  Not Found [IP: 143.204.201.112 443]
Err:12 https://repo.windscribe.com/ubuntu bionic InRelease
  Temporary failure resolving 'repo.windscribe.com'
Reading package lists... Done         
E: The repository 'https://cloud.r-project.org/bin/linux/ubuntu bionic-cran Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'https://cloud.r-project.org/bin/linux/ubuntu focal-cran36/ Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

can anyone please help me out ?

Answer 1

You didn't specify which version of Ubuntu you are running, but this guide might be useful.

In short, first install transport ´sudo apt install apt-transport-https software-properties-common´

Then add their keys to your apt-repository

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys E298A3A825C0D65DFD57CBB651716619E084DAB9

Remove the other listings of R, and then add this instead

sudo add-apt-repository 'deb https://cloud.r-project.org/bin/linux/ubuntu bionic-cran35/'

Then you can install r-base as usual with

sudo apt update
sudo apt install r-base

Check that you have installed R correctly with R --version

Answer 2

Today I found in keyserv.ubuntu.com a new key:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 95c0faf38db3ccad0c080a7bdc78b2ddeabc47b7.