Rare €2 coins?

Hello everyone, and thanks to anyone who could shed some light on my questions... :)

So here it is, right now I'm keeping the 2€ coins that seem strange to me and that I've never seen before..
I have 3 of the 2€ coins that seem suspicious :)

- I have one from 2015, it says letzebuerg, there’s a "half" head, I think it’s a man. This coin seemed strange to me because the 12 stars surrounding the design are bigger than usual..

- Another one is from 2002, it makes me think of Julius Caesar, he has a laurel crown

- Then, I have another coin from 2018 I think... It shows 3 men, one of them is sitting at a desk writing something, and the other two are next to him watching.. it says "costituzione" on top, and below it says "consicura coscienza 1948-2018", according to my research it’s an Italian commemorative coin celebrating the 50th anniversary of the Italian constitution :o

And as a little bonus, I also want to tell you about another 1€ coin this time, it features a profile head of a man, this head looks like it’s in relief, I don’t know if you get what I mean lol.... on the side it says "2014 william Alexander koning der Nederlanden", if I'm not mistaken it’s written so small...

There you go, I wanted to know their value, if I should keep them or put them back in my wallet.. thanks :)