when you open provided zip file, you realize the files are from far 2017, the main reason that
npm install - fails
because in 2020 most of us are using newer versions of node (my node v. 12.16.3),
and this ol boy runs perfectly on node 9.0.0 from 2017-10-31. so you need to downgrade your node to older version. Thankfully we have nvm tool for easy switch between versions. In terminal run:
wget -qO- https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.3/install.sh | bash
(but as aware user, always examine .sh files before opening them)
now run, to test if the nvm was installed
command -v nvm
#expected output: nvm
if command -v nvm not returning nvm , edit your ~/.bashrc or ~/.zshrc,
by adding next
export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh" # This loads nvm
[ -s "$NVM_DIR/bash_completion" ] && \. "$NVM_DIR/bash_completion" # This loads nvm bash_completion
that should work, if not I’ll leave the article.
in your IDE, open unzipped folder with project, open terminal IDE and in root type:
node -v
will return your current node version
nvm install 9.0.0
will install node 9.0.0 from 2017-10-31
node -v
now you are on 9.0.0
npm i
now you have all the packets with no no errors this time 
& no package.JSON edits
you’ll take it from here 