Successfully download R and Rstudio on ubuntu 18.04, but can't open it,enven on web(8787)

I want to use Rstudio on cloud server, and I successfully download R and Rstudio on ubuntu 18.04, but can't open it. I think it is because of the wrong environment variable. And I don't know what to do next.

mengfei@iZ2zeh7tqthaheqrfl87z2Z:/root$ R
R version 4.1.1 (2021-08-10) -- "Kick Things"
Copyright (C) 2021 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.
Natural language support but running in an English locale
R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

mengfei@iZ2zeh7tqthaheqrfl87z2Z:/root$ rstudio-server verify-installation
Server is running and must be stopped before running verify-installation

mengfei@iZ2zeh7tqthaheqrfl87z2Z:/root$ rstudio
rstudio: command not found

mengfei@iZ2zeh7tqthaheqrfl87z2Z:/root$ export $PATH
bash: export: `/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin': not a valid identifier

root@iZ2zeh7tqthaheqrfl87z2Z:~# which rstudio-server
/usr/sbin/rstudio-server

And I see somneone said it is because of space symbol in PATH, I checked it twice by vi .bashrc, there was no space in PATH.

Hope for your reply. Thank you.

Technically RStudio and RStudio Server are different software products. The first works on systems with GUI, the second works headless and provides web-interface.

For cloud environment I expect that you need the RStudio Server installation, so below are the steps:

1. Installation of R

   • using packages from official repositories

     sudo apt-get update
     sudo apt-get install r-base-dev
     

   • using packages from CRAN

     sudo apt install --no-install-recommends software-properties-common dirmngr
     wget -qO- https://cloud.r-project.org/bin/linux/ubuntu/marutter_pubkey.asc | sudo tee -a /etc/apt/trusted.gpg.d/cran_ubuntu_key.asc
     sudo add-apt-repository "deb https://cloud.r-project.org/bin/linux/ubuntu $(lsb_release -cs)-cran40/"
     sudo apt install --no-install-recommends r-base
     

2. Installation of RStudio Server

   cd ~/Downloads
   wget -c https://download2.rstudio.org/server/debian9/x86_64/rstudio-server-1.4.1717-amd64.deb
   sudo apt install ./rstudio-server-1.4.1717-amd64.deb
   

   Note: you may also need to install build-essential package on server to get R packages normally compiled when running commands like R -e "install.packages('bookdown')".

3. Connecting to RStudio Server - open web-browser and point it to http://localhost:8787 (replace localhost with IP or public domain name).

Optionally you can install RStudio desktop by

cd ~/Downloads
wget -c https://download1.rstudio.org/desktop/bionic/amd64/rstudio-1.4.1717-amd64.deb
sudo apt-get install ./rstudio-1.4.1717-amd64.deb

but I'm not sure how it is useful in cloud environment.

References:

• https://cloud.r-project.org/bin/linux/ubuntu/
• https://www.rstudio.com/products/rstudio/download-server/debian-ubuntu/
• https://support.rstudio.com/hc/en-us/articles/200552306-Getting-Started