I suspect this was drawn entirely by hand as it predates the era of digital design.
You could do something similar using Photoshop and Illustrator together.
First in Photoshop, create a slightly blurred image of some white text on a 50% grey background, make sure the layers are flattened, and that you have the foreground colour set to black and the ...
Photopea can edit this. I just tried it.
The words pop and candy have two text layers each, so you have to double click the "T" icon in the layers panel for each text layer associated with it, and retype the words.
GIMP doesn't support Photoshop layer effects, so this won't work in GIMP. Although that's not to say you couldn't create something ...