Hello,
First of all thanks for choosing our Theme, we are glad to be you in the WoodMart WordPress family :-).
1) Because the menu is set as a mobile menu and main navigation from Appearance >> Menus.
Mobile displays the menu that is set as the mobile menu from Appearance >> Menus.
Screenshot for Clarification: https://ibb.co/48LBzv5
2) Please provide with some relevant screenshot of the specific area of the header you are trying to change the color to check it myself and help you out accordingly, it seems that you are not selecting the correct header to color.
3) To delete recent posts from the footer you need to Go to Appearance >> widgets >> Edit footer column 2.
Screenshot for Clarification: https://ibb.co/pQXKMMC
4) Please provide a relevant screenshot of the specific area where you want to delete the menu. Because currently there is no such menu on your website.
Screenshot for Clarification: https://ibb.co/qp5xnZf
5 & 7) For the icons please make sure that you have set both the addresses same as in our documentation: https://xtemos.com/docs/woodmart/icons-has-been-disappeared/
Then Go to Woodmart >> CSS Generator >> Generate CSS file.
Clear cache and check back.
6) To Remove payments you need to Go to Theme Settings >> Footer >> Copyright text.
Screenshot for Clarification: https://ibb.co/tpXnqtg
Best Regards.