Mamp "error establishing database connection"

I’m working on my 3rd WP website and am experiencing a problem with Mamp. I have the WP files in htdocs, for some reason mysql had been giving me a problem but it appears to be working now. However, the Mamp start page is still not loading and is telling me that safari can’t open the page because the address isn’t valid. If I erase “Mamp” from the URL, it will take me to the page to create the WP-config file but won’t let me actually create the file because there is an error establishing a database connection. I don’t have a ton of experience with Mamp and WP yet, so I am stuck and getting a little frustrated. Any help is much appreciated.