Generally toes don't need filing to smooth them as it really can damage the nail plate and encourage fungal nail/bacterial infections more easily. I have probably only filed one or two clients odd nails that's all if there is a significant ridge on them. I was never taught to buff toes or fingernails receiving a normal manicure or pedicure just to clarify.
However buffing with a sponge buffer ( gold or pink one) as is used in gel nails is done, but I don't buff toes that are having gel applied....that's just my way and I prefer it. You must do as the course says naturally.
Little toe nails have sometimes an extra bit of hard nail just on the outer edge of the nail, which is more like a hard callus. It can become quite painful. I trim carefully with cuticle nippers or use my Mr. Pumice very carefully to remove it. I am an experienced pedicurist so until you know what you are doing please don't try the nippers.
HTH