formula to breastfeeding

Alana • Married | TTC #3 w/ APS | Mommy to 1 girl 👧🏼 & 1 boy 👦🏼 & 3 angels 👼🏼 |
I've been formula feeding for various reasons but I want to breast feed.. she's finally latching *i think* but my supply is crap and she's 5.2 weeks old is it too late? How can I be sure she's getting fed enough ? Will she suckle if nothing's coming out? I'm very lost but don't want to give up