How to get values from Database and show them in label text?

I want to get the value of DOWNLINE and BALANCE and show it in app. When a user login and click refresh button then their DOWNLINE and BALANCE will be shown

You have faile dto set project bucket .

When refresh click
set firebase project bucket as 3341768958
Call firebase tag value DOWNLINE
Call firebase tag value BALANCE

Others things are let it be

when a person uses the app he registers in it so um70 this is his user name as a bucket now how can I call his own user name as a bucket to show the values in another Screen

save his user name in tinydb and in next screen just call this user name as firebase tag…