Hi there, 
unfortunately, I am not able to uninstall Node.JS completely. I already tried it using Octopi, and now there is nothing left to uninstall. But when I type in the console “node -v” the output is always “v10.6.0”. Why is that? Cannot find solutions even using google. Please help.
Search for installed node packages
$ pacman -Qs node
local/nodejs 14.9.0-1
Evented I/O for V8 javascript
Then uninstall the package
Or you can query system for the node binary
$ which node
/usr/bin/node
Then query which package owns the file
pacman -Qo /usr/bin/node
Then remove the package
Hi linux-aarhus,
thank you for the quick reply.
Now the system tells me: error: No package owns /usr/local/bin/node
So how to uninstall in that case?
That means you removed nodejs package
The only way to get files into /usr/local/bin - is something you have done manually.
A local make of a source package can do this e.g.
$ configure && make && sudo make install
So to remove it - you will to use the same source package - and run
$ sudo make uninstall
Or perhaps a node version manager was used.
https://docs.npmjs.com/downloading-and-installing-node-js-and-npm
yeah, I recently installed nodeJs through nvm much easier to get a certain version of node, if you want to use them.
I see I have a lot to learn. 
Thank you all for your help. I appreciate it very much.