Change modules in homepage

Hi to everyone!
Idk if it's a stupid question, but I've spent hours trying to accomplish: I'd like the homepage of unregistered to show what my website is. So I could use one less login plugin on the homepage (I'd go for the right panel login form, whilst changing the central module, maybe with an article or simple text).
How can I get this done?

Joomla module display is entirely based off menu assignment. So you should be able to edit your module and under Menu Assignment strictly assign it to your home page or to be excluded from your home page.

Thank you for replying, but it's not what I meant.
See the attachment: I'd like to get rid of the login form only in the center of the page (which shows it twice, in center and right side).
Instead of that I'd like to write something 

That's the login page. You can't get rid of that. The right login form is your login module and recommend just adjusting its menu assignment so it doesn't display on the login page.

But can I adjust its menu assignment so the CENTRAL login form doesn't display on the login page?
And maybe show some text instead?
I tried but didn't figure how

The login form in the center of the page is your login page. You are on the login page so you of course can't get rid of the login page when you're on it.

Normally you'd just not display your login module on the login page. To do that edit your login module in Content > Site Modules then under Menu Assignment set "Module Assignment" to "On all pages except those selected" next click "None" for "Assign to Menu Items" now just find your login page menu item and select its checkbox then save. This will hide the login module when viewing the login page.