What is a good carb intake to lose weight and keep blood sugar from dropping too low? This happened with a fad diet I tried. I am not a diabetic.

QUALITY NOT QUANTITY. The more complex carbs are better in this regard. White flour carbs are very quickly absorbed and can cause a sudden surge in Insulin levels, which will invariably drop you like a bad marriage within a few hours. More complex carbs will get absorbed slower, hence preventing or decreasing Insulin spikes. As a rule of thumb, never eat carbs by themselves, no more than 20-30 grams per meal.
Many ways. I usually advise my patients to do a 3 day diary on everything they eat and drink including water. Make an appointment with a dietician bring the diary and make a plan for 1, 200 cal daily on sedentaru days and 1, 500 cal for active days (at least 1 hr of physical activity3-4 days a week). Total carbohydrates only to be 30% of caloric intake.
50-60% 50% to 60% of your calories as carbohydrates. If you take your carbohydrate as a complex carbohydrate instead of processed grains, and take it with a protein- there is a better chance you will keep your blood sugar elevated. Example- banana and peanut butter- or whole grain high fiber bread ( 2 slices) and cheese.