1 - The parts are interlocking, but it could depend on the tolerance of your printer
2 - The feet are locked with cubes that may need force to be inserted. If they do not fit, just print some cubes of the appropriate size (printer tollerance).
3 - the "junction" has a narrow part that fits into the upper part of the drawer. If there are problems due to the tolerance of the printer, the size of the printer can be slightly increased (+ 0.5%)
4 - superglue can solves problems
Recommended filament PETG or PLA +
i've printed it with noozle 0.4, layer height 0.32 and all speed 110 mm / s
The author hasn't provided the model origin yet.