If you installed expo before, please temporary do not upgrade to their latest version.
Please do the following steps to resolve this issue:
Step 1: Open terminal
Step 2: Run npm uninstall expo-cli
Step 3: Run expo-cli -g –unsafe-perm=true
Step 4: Run ls -la ~/
If you see .profile on your terminal, please run nano ~/.profile
Otherwise, please run nano ~/.bash_profile
Step 5: Put export NODE_PATH=/usr/local/lib/node_modules to the end of the file. Then press control + x
Terminal will ask for Save modified buffer (ANSWERING “No” WILL DESTROY CHANGES) => Please press y then Press Enter
Step 6: Run source ~/.bash_profile
Now, run expo –help, this command line should work. And you can build app by following https://documentation.wilcity.com/ => Wilcity App