Here the "true vine" is a metaphor. Jesus compares himself to a vine or a vine stem. He is the source of life that causes people to live in a way that pleases God. Alternate translation: "I am like a vine that produces good fruit" (See: [[rc://en/ta/man/translate/figs-metaphor]])
The "gardener" is a metaphor. A "gardener" is a person who takes care of the vine to ensure it is as fruitful as possible. Alternate translation: "my Father is like a gardener" (See: [[rc://en/ta/man/translate/figs-metaphor]])