Need help on Adsense placement

Good day,

I'm just wondering which file/s should I edit (in the theme editor) if I want my site (see signature) to have Adsense placed as follows:

1. below the navigation bar
2. just above the "Recent Videos"
3. just above "See recent articles in the archive"

Thank you.

P.S. Is it also a good spot to place Adsense? Thanks!

Pat

 

Any help? I'm willing to pay. Should I post this in another section?

Thank you.

Pat