Image Alt text on the Hyde template not working and file renaming question

Hi all,

I am using the Hyde template. I'm trying to do two things:

1) change the file names of my images in the gallery on front page and product images (without having to re upload them all). I have tried going to the options tab in the image settings (as some have suggested) but there is no option there for 'file name' ..only an image URL link (tried changing that but doesn't make a difference to the file name). Screenshot attached.

2) Add alt-text to the gallery images on the front page. I have followed the instructions by squarespace on adding alt-text to images https://support.squarespace.com/hc/en-us/articles/206542357 but I can't get it to work at all. The text shows across the image when I write it in the Title and Description box. I want the text to be hidden, purely there as alt-text. Am I doing something wrong? screenshot attached my help to explain...

Site is erikahansendesign.com incase that is helpful. Thanks all :)

@rachelmaley thanks for the reply but i'd rather figure it out myself as it must be simple to do :)

@Paul2009 hope you don't mind the tag - do you have any ideas why this does not work as it says in the squarespace tutorial?