How hard a language is depends on your native language. People from Sinoxenic culture will have an easier time acquiring vocabulary. People who speak a tonal language will have an easier time learning Chinese tones. Those whose native language is neither Sinoxenic nor tonal will have a more difficult time learning Chinese. Because of the above and the thousands of Characters needed.

chinese and japanese has many word tha english

Yes，so I think actually English is not very hard on the words level. But it is not easy for us to fully understand it on the grammar level which is very different with Chinese.