I changed my permalinks and broke my dashboard

I’m sorry to bother you all, I am very green at this. I know this subject has been dealt with before, by and for people with more knowledge than me, I’m asking for help in baby language please

I had installed WordPress and Woocommerce, spent the whole evening building a site for my wife, then decided (stupidly) to change both of the permalinks. The site disappeared instantly.

I tried changing the permalinks back again on the settings page, no joy.

I navigated away from the settings page and found that the whole WordPress dashboard had been replaced with a 404 “page not found”. Now I’ve even lost access to the settings page, I have no dashboard at all.

I can see the wordpress files and folders in my GoDaddy file manager so I know that the information is largely still there. Perhaps there’s a way to edit one of the files through the file manager page?

Please can someone give me a step-by-step on how to make it work again?

Thank you! Ben