Online Store on the front-end + firebase is real?

Question

Google

A friend asks to write him a simple online store (maybe even a selling landing page). (We will assume that he has not heard about programming).
I know well:
1) javascript (native and jquery),
2) a little rummage in firebase,
3) react (pure react without redux, but if necessary I will study because I will do it anyway), I also tried to learn angular , but after mastering the tutorial (mobile phone filter), I realized that I don't really like angular.
with html, css everything is fine of course.
From the site you need: send letters to email in the form. (I don’t know how to implement it, because I’m zero in the back-end).
Authorization. (with the help of firebase I will do it).
Basket (I think it is quite possible to figure out the front ende).
Attach a payment system (I have no idea how to do it);
So far, all I've done is create sliders and stuff like that.
Wrote a couple of static landings without interaction with the server.
Or maybe just send him to study CMS?
I will be glad to any advice.

Answer 1

A CMS is not needed for a Landing Page , it is a CMS, and those who do it on WordPress usually do not understand that this is wrong .
In this case, nothing remains of WP, as a result, it is just a bunch of scripts that reach for LP and only take up space on the hosting and load it.
An online store has its own CMS, but you can do it your way if you don’t suffer from it, because complete ignorance of the back-end is punishable ...
tasks, though... the taste and color ).
What you described is quite realizable, why not? The main thing is how it will be convenient for you to create, and for a friend to support.
First, decide what exactly you or a friend need: an online store or a (selling) LP, because these are completely different things.
You can also read about SSI, but it is unlikely that it will be useful in your case.

Answer 2

Or maybe just send him to study CMS?

If there is a payment, there must be a base, the base is the back-end.
Therefore, let it be better to immediately teach CMS Joomla! + Joomshopping and then he himself on this engine - makes any of his Wishlist.

Answer 3

In any case, you need a back-end, how are you going to create goods, make samples and place orders only at the front?