can't connect to wordpress admin pannel

I recently installed wordpress by drag-dropping the whole wordpress document on my website. I connected to it to install and had to click a ”wordpress” link. clicked it and I then installed everything.

After, I tried to delete the document so that people that come to my site wouldn’T need to click the little wordpress link. I transfered the whole wordpress files to my pc, deleted them from my website and put them back when they were not in a wordpress document. It worked well.

I then installed the sandbox theme. 3-4 minutes later, they told me that wordpress did not have the good ftp adress…

now, I can’T log to the admin pannel to change my settings and check if my ftp adress is the good one (I think it is tho)
anybody can help me?