I'm a bit confuse with this web stuff,what do you actually need to know/understand before creating or developing a website.tnx

Question

Web

Answer 1

for static simple websites: html and css will work
for dynamic website with user interactivity: html, css, JavaScript, PHP and sql will be enough.
these are for basics. ..in advance lots of framework available to simplify your work but before that you need to know these.

Answer 2

It depends on what you want to do. If you want to do the fastest way : HTML is mandatory, CSS also in order to have the presentation you want.

In the first step of HTML course, you can see this indication about modern web design :
- HTML: Structure
- CSS: Presentation
- JavaScript: Behavior
- PHP or similar: Backend
- CMS: Content Management

If you're looking after a way to just do a simple static website, HTML and CSS is enough.
Hope it will help