Website Design Queries

1.What kind of website suites to our business?Which type of layout and colour theme I select?
2.How to make my website responsive?
https://www.youtube.com/watch?v=Mk21Khduk6c
https://www.youtube.com/watch?v=8YS54x2UW9Y
2.Sliders?
3.Navigation Bar
4.Breadcrumb
5.Forms
6.Vertical or Horizontal Mega Dropdown Navigation Bar