How did the western European countries get developed much faster than the rest of the world? Did they do it through colonisation? The UK and France had a significant number of colonies but did Germany and Italy have many?

I would suggest Alan Taylor's American Colonies as a starting point.

But in essence, Europe in general was highly competitve from the 1400s to mid 1900s.

Dutch, portuguese and spanish colonies centered in the americas starting in late 1400s, early 1500s.

English and french colonies in the late 1500s to early 1600s in america.

German and italian colonies appeared in africa predominantly in the 1800s. The dutch were there too in that time period also, among others.