Post Images not displaying anywhere!

hello,

I just installed the ‘Nile’ theme, a child theme of Alexandria, and I haven’t been able to get my featured images to display on the posts page or on the home page. Website is https://kellysantos.org/

I saw many posts about this in the forum last year, here it is the link

And I tried putting the code they mentioned in that link in my theme, and it didn’t work. I’m not sure if I’m using the right code and/or if I’m putting it in the right place. I also used the info from here to try and figure out, but I’m a beginner coder.

Any help would be most appreciated as I really love this theme.

thnks!