How to change an image in javascript? src not working

Hello!
I’ve never used javascript before and I’m having so much trouble figuring out how to change the source of one of my image elements. Maybe it’s a syntax issue? I’ve tried multiple different urls and nothing has worked. When the function is called, everything inside it works accept for this piece - it just keeps the original picture. The picture I’m trying to change is an image element inside of a div which is inside of a section which is inside of the body. The code is in: ‘workbench’ page custom code > ‘before tag’ > bottom switch function. My image element ID is “layer1”. I need to be able to change the image on click and all my images are in the assets section of the project. The url I have in my code is the one from the assets section. The button that performs the function(showSelected) is as follows:

doubleNotched.addEventListener(‘click’, (event) => {
lastSelected = doubleNotched;
layer1.style.display = “inline-block”;
showSelected();
});

Here is my read only link, thanks for any help!

My read only link