Do you need a company to publish ebook and actual book ?

You're doing something wrong. Amazon will happily let you publish an ebook under your own name on their KDP platform (Kindle Direct Publishing), without the need for any third party to be involved. You can do the same on CreateSpace for print books. (KDP have recently started offering the ability to publish print books as well, but I haven't tried that yet. I'm waiting for braver and more impatient people to find the bugs in it.)

Yes

It is called vanity publishing. Nobody takes an author serious who self-publishes, unless they've already established that they can draw an audience and be published with an actual publisher. The term "published author" means you have a publishing company.

We live in an age when anyone can publish ebooks or print on demand and pay nothing. However, these books, unless pornography, rarely sell enough to make it worth while. Unless you operate a cultm are a celebrity, or sell fake conspiracies to conservatives there isn't much of a market which will pay money for amateur works, spurned by real publishers. The few examples of authors who have surmounted this obstacle are all of people who had large online followings and their "victory" is basically having a real publisher pick up their work.

If you self-publish and tell people you're a published author, you're a joke.

Anyone can publish an ebook by following the instructions to upload an ebook. You do not have to name a company and you can get an ISBN through amazon or else be redirected to a site where you can buy an ISBN number. You can use amazon's affiliate CreateSpace to self-publish a print version of the book.

You're confusing some things.

A standard publisher like Daw or Heritage is a company that pays an author for manuscripts, they take care of all the printing, the advertising, the marketing, the storage and shipping and get the book onto the catalog that bookstores and libraries order from. They basically handle everyting once they purchase the manuscript.

Then there are Vanity Presses, which YOU pay to have copies of your book printed up. They ship them to you and that's all they do. They will not market your book, they don't promote it in any way, can't get it into libraries or bookstores - YOU do all that work. You store your books and you basically just paid a 'printer' to do what they do, print up your book. This is a bad way to go about things and costs you money.

The third option which a lot of people are going with, is to work with a print on demand printer -- Amazon has one associated with it's company called CreateSpace. Barnes & Noble had their own print on demand company, and you can find independent companies like lulu.com by just googling for 'print on demand self publishing. The author pays nothing. They upload their manuscript to the website, set the price, and there is no out of pocket expense for this. While the sites DO NOT put your book on the national catalog for bookstores and libraries to order from, they do connect with Amazon, Barnes & Noble and other sites where your book can be sold though for anyone googling your book. THEY get paid by taking the portion of money it costs them to print and ship your book when it's ordered. YOU would be taking that price owed to the site into consideration when you set your book's price. The books are printed as needed, and you aren't stuck with trying to store or ship hundreds of books at your end.

With CreateSpace and Amazon, both of them take a cut. For instance -- If you price your book at $5, your cut of that is going to be .84 cents. The rest goes to CreateSpace for printing and shipping costs, and Amazon's listing fee which is separate. So pricing above $5 would get you more money.