Jesus is talking to a group of people about what they as individuals should or should not do. The instances of "you" and "your" are all singular, but in some languages they may need to be plural. (See: [[rc://en/ta/man/jit/figs-you]])
This is a metaphor. Possible meanings are 1) the eye is like a lamp because it enables a person to see things, or 2) the eye is like a lamp shining on a person's body because it shows what the person is really like. Alternate translation: "A person's eyes are like a lamp for his body" (See: [[rc://en/ta/man/jit/figs-metaphor]])
# if your eye is good, the whole body is filled with light
Possible meanings are 1) "if your eye is good, it fills your body with light" or 2) "if your eye is good, it shows that your body is filled with light."
# if your eye is good
Possible meanings are "if your eye is noble" or "if your eye sees clearly." Jesus speaks of the eye to talk about what a person thinks about and wants. Possible meanings of the metaphor are 1) "if you are generous" or 2) "if you look at and want at what is good" (See: [[rc://en/ta/man/jit/figs-metaphor]])