Hi Lee Ann!
If you're just beginning with free weights, a good place to start is in the 12 - 15 rep range. That means you want to pick a weight that becomes very difficult somewhere between 12 and 15 reps. If you get to 15 and still can keep going, you know to pick a heavier weight the next time. If you're struggling and can't make it to 12, go lighter next set.
The weight you'll be starting with will be different for each muscle group you're exercising. And of course, at lot depends on how strong you are naturally! Women tend to be strongest in their backs, legs, and biceps and weaker in their chest, shoulders, and triceps but it's really variable.
When I had a new gym member, I'd guesstimate what weight to start them at like this:
Back rows: 10#
Chest press: 8#
Shoulder press: 5 or 8#
Bicep curls: 8#
Triceps: 5#
Maybe that will give you a starting point and you can then see how you do in the 12- 15 rep range?
Good luck! It's a world of fun.