What species of tortoise?
Yes they will eat plants you put into an indoor enclosure.
Is what true? Can they carry salmonella? Yes they can. Any animal can. Salmonella is all over your phone, on your computer keyboard, and in most of the chicken you cook. How to control it? Wash your hands after touching your tortoise, or raw chicken, and don't lick either.
I When I am drying Zola, after a soak, I feel a strong urge to kiss his cute puckered little vent. I haven't yet succumbed, but one day I'm sure I will. And I have "shared air " with him many times when I am holding him and his little face is right up against mine....but biting is fine, esp your computer keyboard.