submenu and images not showing up in github but locally both work fine

[pupaimadhusree]

I'm new to this and unsure how to present the problem. Any help would be appreciated. My index.html file that I made using a bootstrap 4 package runs properly locally, but when I commit the files to Github, the resulting site shows neither the images nor the submenu. The issue is the same for all browsers. The same files were cloned in a different repository and it worked there. How do I fix this? Thanks.