Some points to remember when uploading "copied" websites...
What I mean by "copied" is when you are viewing a site and do a "select all" then "copy" - you may get the website copied or... you may only get css code that doesn't work for YOU because of the linking in the css code. Besides, in most instances it is against Copy-write Laws to just copy someone's site.
If you have legal copy privileges then the "source" html should be available to you. THAT is the code you need to copy... and save to NotePad (or the equivalent on a Mac) first, then from Notepad to you html editor such as FrontPage, Dreamwaever, or Komposer. NOTE: Have you editor in the "html" view when you paste.
Then preview the page. If it looks OK you should be good to upload to your server... assuming you changed the appropriate links to yours on that page.
Next thing to think about is WHERE you want to post that page. You can have ONLY ONE "index.htm" or "index.html" page in a directory or sub-directory. For example, if your new page was about Dog Training and your web site is ILoveFurryPets.com (my apologies if that is an actual website) then you would have to name the new page something other than "index.
" such as dogtaraining.html OR create a sub-directory (easy to do in Filezilla) called Dog Training and upload the file to THAT directory and rename it to index.html.
Some sites include code that may not be compatible with your hosting service... it's rare but does happen.
Hope this was of some help.