Diffusion and effusion are not the same. Diffusion refers to the movement of molecules from regions of high concentration towards a region of lower concentration. When the temperature is higher, the rate of diffusion is high and vice versa.
An excellent example of this is observed at the Gas station, at first you might not be able to perceive gasoline smell, but the moment it diffuses into the air, you can smell it. Effusion refers to the movement of molecules through a small hole in a membrane. It is the escape of gas from a container.
Some people assume that effusion and diffusion are the same, but this is not true. Diffusion is known to be the movement of particles from one place to another place that comes with a higher temperature. An example of this is the smell of perfume.
When you spray it, you do not immediately smell it, but when you do, you know that the particles have already diffused successfully. Effusion refers to the movement of the glass particles through a small hole. Even though there are differences between the two, it cannot be denied that they are similar to each other because of the similarities in the movement of gas and gas behavior.