can i really design a good website with html alone without the help of other programming language?
Well, you need CSS to do design, otherwise you’re stuck with how HTML renders by default. And a website is just the little bit of an application that a user can see in a browser – that might be all there is, generally it isn’t though. You can’t really say it’s “good” or not – you can make anything look beautiful using just HTML and CSS, doesn’t mean it’s useful or functional
You can definitely create beautiful sites with HTML alone, animations and all. What you can’t do is get it to respond to clicks or keyboard events or otherwise respond to input other than clicking on links. So it’ll just sit there and look pretty, which is actually just fine for a lot of pages.