I need to lose weight. would strength training be a good idea?

Yes: Yes, but not the best.This is taking one desperate side to a problem that requieres good planning and target set on realistic time, plus appropriate diet.

That is one part of: a smart weight loss program. Eat healthfully. Try to eat at least 5 servings of vegetables & 4 of fruit per day. Increase nutritional fiber. Avoid refined sugar & junk carbohydrates. Avoid alcohol, sweetened juices, soda & caffeinated beverages. Aim for 7.5 to 8 hrs of sleep / night. Hydrate w at least 64 oz of water / day. Calories burned must > calories consumed. Do cardio & weight training.