Hi, yes you have to collect the weapon first at the end of Level 1 down to the left after jumping through the old house and past the enimies there is a sleeping person which activates the weapon when you collect them.
the first obstacle...jumping from house to house or through the bigger complex? it is quite tricky to be fair....here is a walkthough video: https://www.youtube.com/watch?v=CP2XUy4xCLA
nonetheless thanks for playing ^^ I hope you maybe can get past the obstacle at some point!