If you know programming in html / css and there is acces to the code for internet (files by exporting to hard drive for instance), yes then you or somebody else can make changes.

These will not be in your project offcource, just on the exported files.

Hope this is what you mean....

BR A

No matter if my website is host in Godaddy.com. 

If your site is uploaded then changes to files can only by done with login and password.

or if hacked or by emplyees of the hosting party, but they don't do that without proper ground offcource.