It’s going to depend greatly based on the type of tomato you have. Indeterminate tomatoes (the vining ones) will fruit at different times, so you could enjoy some tomatoes now, and others two months later from the same plant. Determinate tomatoes will all fruit at once, giving you one large harvest. Most tomatoes need 65-90 days from seed before you’ll begin to see any tomatoes. Once you see a flower, that will turn into a tomato fruit in about 15-20 days.