I need to create mockup. There is a text forms and also I need drop down list and checkbox.. How I can find these things in Muse? There is only sample contact form,where I see checkbox,but this form is inseparable..
You may want to check out usingAdobe FormsCentral, Jotform, or Wufoo and inserting them via Object > Insert HTML as an alternative from the Muse forms, as those forms will have the lists, buttons, and checkboxes you're looking for.
Another way if you are publishing your site to Business Catalyst, then you can create forms in BC admin section and copy the form HTML in Muse page which will render the from that you have created in BC in your Muse site page.