The problem with registration in ADE

Hello! I bought a book on Google Books, downloaded it to my Mac, and now I want to transfer it to my wife's Pocketbook. I installed the latest version of Adobe Digital Editions, but when I try to load the book for conversion, the program throws an error. I registered with my Adobe account, but I suspect that since Google is the book provider, I should log in with the Google account I used to purchase the book. However, I can't log into my Google account in ADE—it keeps saying the password is incorrect, even though I'm entering it correctly. As a result, I can't do anything. The ADE program itself also looks strange. I'm attaching screenshots. I have already contacted support but have not yet received a clear positive response to solve the problem. I still don't understand how to change the language in the ADE program. The program itself looks odd; there are no "File" or other tabs. I'm not sure if this is relevant, but I'll mention it.