Help with plugin

Helle everyone! I have some troubles with WordPress and have no idea what to do right now. I cannot acces the dashboard and when I try to open the login page it just come up as blank.
I was trying to install a new plugin before this happened. I searched online but only find solutions to use FTP but I am not sure if I can access it since i am not the owner of the site, just have the login information.
Can someone please help with this issue? I am panicking right now…

 

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