Product landing page. Please help

Good day. please i really need help. I need someone to help me to look into this code( and explain to me what need to do and what i have done wrong. Im really confused.

class “nav-link”

what’s your class’s name?

Thanks for the prompt response, I deeply appreciate. It really helped. But with all humility, something is still wrong somewhere. I have not been able to embed a video.
Kindly help