general help and tips on developing ecommerce webpage

General context:
I'm trying to learn web-development while doing my friend a favor with their website.
At my job I've used Oracle ADF but I want to start using something versatile like html+css+js.
Time is not really an issue (got 6 months to do it) so I don't realle need a framework to do the work for me.

The task:
Developing a ecommerce webpage for a small hipster-ish shop, that uses mercadoPago. I wanted to use plain html+css+js for front end and node-js + mysql for backend.

Questions: Would the use of certain frameworks boost/help development without hindering my learning experience?
Should I use another language for backend? Is another combination better?
To update content (like stock o images) would it be better to make admin account on website for client or a desktop app?
What are the minimun functionalities I should aim at? What checkpoints should I set to myself?
Feel free to give me any advice you think would be useful

via arilei