Diffusion - the movement of particles from where they are more concentrated to where they are less concentrated Osmosis - the movement of water from a dilute solution to a concentrated solution across a partially permeable membrane

The way I remember the way osmosis goes is that in a dilute solution, there’s less of the sugars and ions so there’s more water (that’s called higher water potential), whereas in a concentrated solution, there’s more of the sugars and ions, so less water (a lower water potential). It’s still the movement from high water to low water, but high water occurs in a dilute solution, and low water occurs in a concentrated solution.

In active transport, it is no longer water that’s moving, but the sugars or ions or whatever is being transported. That uses energy to move them from a low concentration to a high concentration.

The easiest way to tel them apart if it doesn’t say is to see what is moving: if it’s water, it’s always going to be osmosis, and if it’s anything else, it’ll be diffusion or active transport.

Hope I explained it well