Can you please answer a few questions about CSS and give some layout tips?

Question

css

I'm new to layout, so I'm asking for advice from more experienced layout designers:
1. Should I set the flex display for the div in which all other elements are located. Example:

<div class="conteiner">
<header>
.....
</header>
<aside>
......
</aside>
<article>
......
</article>
</div

Do you need to set display flex for the container if you want to layout the site on flexbox or not?
2. Is it possible to make a site fully responsive on Flexbox without using media queries?
3. Advise on what to learn next after HTML and CSS. I want to be a freelancer. I don’t know what to learn next CMS, JavaScript or something else.
Hope for help.

Answer 1

1. depending on what you need
2. you can, but I would not overload proj with flexes. I read somewhere on this topic that the browser can have lags if there are a lot of flexes.
3. you need to go to the galley and work there for at least a year \ 2. get experience and a base, and then you can go freelancing if you still need it and it will still beckon you with ghostly freedom
4. the word conteiner is a little not it's spelled the way you wrote it