Heat olive oil in a large non-stick skillet over medium heat.
Add the chopped onion and cook for 3 minutes until softened.
Add the minced garlic and cook for 30 seconds until fragrant.
Add the chicken pieces to the skillet and cook for 5-6 minutes until lightly browned and cooked through, stirring occasionally.
Add the diced carrot and zucchini to the skillet and cook for 3 minutes until slightly tender.
Pour in the low sodium chicken broth and bring to a boil.
Add the orzo pasta, dried oregano, salt, and black pepper to the skillet.
Reduce heat to medium-low and simmer uncovered for 10-12 minutes, stirring occasionally, until the orzo is tender and most of the liquid is absorbed.
Stir in the chopped spinach and cook for an additional 1-2 minutes until wilted.
Remove the skillet from heat and stir in fresh lemon juice and chopped parsley.
Taste and adjust seasoning if needed before serving.