category/products missing…

hi,moved from twenty-ten to twenty twenty-one as the first-between other issues-was giving low resolution images…Now,trying to customise my site,the only that have achieved was a logo,background image and a main page/shop followed by ”featured products” section…Trying to create a category/products clickable title, that appears at the bottom/footer but its inactive…..the fact that this great theme is missing sidebar is a major drawback…could you please help to add this elementary feature??tried with menus/witzets but created a mess…thank you.

The page I need help with: [log in to see the link]