Most languages with few exceptions are decended from or dialects of other languages
I am no linguist and I cant tell you the difference between a dialect and new language. Many western languages that we speak are called indo-european languages
The basically fall into the Romance Language (Decended from Latin which are Spanish, French Portguese. Romanian Ladino and smaller languages)
And the Germanic Lanaguages which are German, English, Dutch, Swedish, Norse, Yiddish and similar
Romance languages are somewhat mutually intellegible to each other, but the Germanic ones generally are not. A Spanish and Italian Speaker can usually understand each other, however an English and German speaker generally cannot.
However Yiddish / German speakers CAN understand each other.
Words , Lexicon and grammar do not come out of a vaccum.