500 Internal Server Error with Wordpress

[lgblogx1]

Hello, i've been using x10hosting for a couple of weeks and i really love it!
After working on my wordpress site for a while, i encountered an error (500 Internal server error) whenever i tried to access the website.
I didn't edit the source codes except for some CSS, but i did it some days ago and everything was working fine until today.
Today after trying to set up a newsletter the problem first appeared on the website, but i didn't do anything special (just worked a bit with the MailChimp plugin).

Could anyone help me with this please?
Thanks in advance, here is my website: http://lgblog.x10host.com/en_US/

 

[lylex10h]

If you have a .htaccess file, try renaming it to htaccess.txt

 

[lgblogx1]

If you have a .htaccess file, try renaming it to htaccess.txt

Thanks, i did it and it's now working, but only if i disable a multilanguage plugin that allows me to have the website in two languages using (websitename.x10host.com/en or /it).
Could that be the problem? If i activate it just doesn't find the url.
What does the .htaccess file do? Sorry if these are silly questions, i still have to learn a lot.

 

[lgblogx1]

Just tested the website out, found out that there's another problem.
Since i deleted the .htaccess file, i can't access any other pages other than the default one (the homepage), anybody knows how can i fix this?

 

[lylex10h]

Try .htaccess with the default listed at https://codex.wordpress.org/htaccess

If that doesn't work, WP Admin --> Settings --> Permalinks --> Select "Plain" and click [Save Changes]