Use Digital Ocean to create node.js server or creating website on Wordpress?

I'm needing to develop a website for a client and I need to know which way to go.

At first I was thinking have the client pay $5 per month for a Digital Oceal node.js server and I could use that system to 'host' the website myself (am I right? Please correctly me if I'm wrong here - seriously) then register the ip address and tie it to a domain name that will be registered to a domain name service.

OR

Use Wordpress to make my site from there with pure client side JavaScript (I could do it...right? I need correction here as well if I'm wrong) I do not know how to get, when a person goes to username.wordpress.com, some JavaScript inserted into that page and hook into the flow so I could take over with my code from there with React.js

Places to point me to get to the correct resources to get to for adding javascript to execute when a user navigates to username.wordpress.com would be amazing

Realize that I am a programmer.

I can learn more photoshop/sketch type stuff, but for now need to get a handle on the setup of the website to just write the code!

I really need your help. Thanks for your time

~Coty

via Chebli Mohamed