404 Not Found-error when trying to install WordPress

Hello,

I’m trying to install WordPress on https://www.sophieholterman.nl. I followed all the detailed instructions for DirectAdmin, changed the wp-config-sample.php into wp-config.php, created a database on DirectAdmin to send the WordPress-files to, filled in all the right data into wp-config.php (I’m almost sure I did it right), downloaded FileZilla to transfer the files… but it isn’t working. When I visit https://sophieholterman.nl/wp-admin/install.php I see ‘404 Not Found’. Somewhere in between my attempts, I went to ftp://sophieholterman.nl, where I saw a html-code with a sentence in it like ‘PHP does not exist’, or something like that. I tried a little more (used other directories in FileZilla to send my files to) and now ftp://sophieholterman.nl gives a list of files with a title above it saying ‘Index van /’. (van is Dutch for for)

I’ve already sent a message to the host/server/or what it’s called, because the only reason I could think of for this problem is that I don’t know what my Root Directory is.

My question to you: could something else be wrong? What should I do?

I hope you can help me.

Sophie