To get better riding hills you have to....ride hills! Here's a few tips I've learned:

Keep pedaling! Don't just coast down and then huff & puff up after your bike has come to an almost complete stop. You'll be surprised at how much MOMENTUM will get you up the hill! Same for flats - keep pedaling at the same cadence and use your gears.

Concentrate on pedaling in a circle, not just mashing down. (It gives you some thing to think about other than the never ending hill.) Seriously, it does help.

Get your butt back on the seat and use those strong gluteal muscles that we women have.

If you need to stand, shift into a slightly harder gear, stand up & keep your butt back as much as possible. When you need to sit, you can shift back into the easier gear. Standing uses more energy than sitting, so save standing to pop over small steep hills, or when you can't sit & pedal anymore.

When you're sitting, keep your hands on the top of your handlebars. You'll open your chest more & your lungs can expand more easily.

For long, never ending hills, spin. Don't mash. You'll wreck your knees & your lower back. Even if you're going slower than the pack, spin. You'll get faster.

If I think of other things, I'll post again.