Hello, Yaya
Esta is femenin singular demostrative article, similar to "this".
This table is broken -->> Esta mesa está rota.
Está is the form for the third singular person from the verb "estar" (to be).
She is worried -->> Ella está preocupada
He is worried -->> Él está preocupado.
Hope it helped you. Let me know if you need further information,
Regards.