Hello and welcome to the forums!
Photos with flash are normally not recommended for telling gender as it can wash out the true colors and make it tricky to tell. However, in this case, I am 99% sure that this budgie is a girl

If you would like, you can post photos taken in natural light to confirm, but I am fairly certain. She's very cute.
Are you quarantining your new girl before introducing her to your male budgie?
Quarantine IS Necessary!
Additionally, since you will have a mixed gender pair, you will need to do everything possible to discourage breeding. Domestic birds being kept as pets are much healthier and happier if they are not bred. Check out these links below:
When We Don't Want Eggs!
Before You Ever Consider Breeding Your Budgies
Are You Ready To Breed Your Budgies?
A Breeder's Tips for Discouraging Breeding
A Heartfelt Plea to All Members
There are many other helpful links on the forums! Please be sure to read through these to stay updated on the best of budgie care practices
Best wishes! 👋