Hello and welcome to BackYard Chickens!
Glad you joined.
Everyone here is very kind and helpful
Could we get a picture of your brooder setup? As other have said, she has imprinted in you.
If she is wild it would be best to release her once she's grown but that will be difficult since she has already imprinted on you.
Unless you live in Florida, you won't need a permit to keep a wild duckling though.
I suggest getting a few more ducklings around her age. Most TSC have ducklings right now.
If she hadn't already imprinted in you I would suggest taking her to a wildlife rescue.
What are you currently feeding her?

Everyone here is very kind and helpful

Could we get a picture of your brooder setup? As other have said, she has imprinted in you.
If she is wild it would be best to release her once she's grown but that will be difficult since she has already imprinted on you.
Unless you live in Florida, you won't need a permit to keep a wild duckling though.
I suggest getting a few more ducklings around her age. Most TSC have ducklings right now.
If she hadn't already imprinted in you I would suggest taking her to a wildlife rescue.
What are you currently feeding her?