How to make an indexed site?

Question

HTML

Good afternoon.
There is my personal site, self-written, without CMS.
It has been published for about a month, but so far its pages have not been indexed by either Google or Yandex.
The site structure is as follows: main page - links to sections - links to subsections - articles/pages.
Those. there is no nesting, but there are just html pages and links to them.
I decided to make a sitemap, but online analysis gave me only the page that I showed him - i.e. index.html main page.
The content on the site is unique, no SEO methods were applied. Thus, it is not necessary to sin on blocking. Although, maybe I don't know.
Hence the questions:
1) Why is the full sitemap not unloaded?
2) Is it possible and necessary to remove .html at the end of the page address? And how to do it without creating separate directories for each article?
3) Through the webmaster and its Google analogue, I indexed the main page of the site - now when you fill in the exact address of the site, it comes out in the search. Do I really have to upload every page to the webmaster?

Answer 1

1) You need to see what your sitemap gives out
2) you can leave html in principle, there is nothing wrong with that
3) It’s hard to say this problem (so as not to clog the page every time) the sitemap solves it, you specify it once and then resend it in the webmaster (for Google) in case of changes on the site, if the content is interesting and changes often, then the search engine bots themselves will go to the site and see what's new

Answer 2

Can you link to the site itself?

Answer 3

Are there any restrictions in the robots.txt file?