Could you please share us your Site URL so that we can figure out the issue and also please check by deactivating the each plugin one by one. Some plugin that you are using might have affected the theme.
You haven’t set the home page to ‘Front Page Template’. Please set the home page to ‘Front Page Template’ from page editor then only you can use the widgets on templates widget area.
please go through the link (here) to set Front Page Template.