Hello, @mohamed aly,
1.. Go to the Dashboard >> XSTORE >> Theme Options >> Theme Custom CSS and then paste the below code there.
#header li a{font-size:15px !important;}
Then save settings and check back to your site after clearing the browser cache.
Note: In the above code the word 15 is the size you can change it with you want.
2.. Go to the Dashboard >> XSTORE >> Theme Options >> Theme Custom CSS and then paste the below code there.
.woocommerce-shop .sidebar span{font-size:15px !important;}
.woocommerce-shop .sidebar a{font-size:15px !important;}
.woocommerce-shop .sidebar li a{font-size:15px !important;}
Then save settings and check back to your site after clearing the browser cache.
Note: In the above code the word 15 is the size you can change it with you want.
3.. Go to the Dashboard >> XSTORE >> Theme Options >> Theme Custom CSS and then paste the below code there.
.woocommerce-shop .sidebar{border:solid 1px black !important;}
Then save settings and check back to your site after clearing the browser cache.
4.. if you want to show this banner for a category go to Products > Categories > edit the category and add a slider shortcode in the category description.
5.. Actually, to show the vendor list you have to set the vendor list widget in the sidebar from the Appearance >> Widgets.
6.. No, Sorry to say that there is no way to check the admin dashboard of another demo.
I hope you understand.
Regards 8Themes Team.