Beginner With $4-600 budget.

Hello! Recently sold some music equipment and want to put a little bit of the cash towards something new. I'm a beginner and will be taking lessons from my vocal coach and practicing with my setup at home. Want to drop $400 to around $600 for the keyboard itself and then worry about the stand and bench.

What should I get? I tried going to into Guitar Center and trying some stuff out but either out of my price range or seemed kinda eh.

Would love to order something online today.

Any help much appreciated!