Dorado means "golden" and is used to describe something made of or colored like gold.
In the song, ROSALÍA sings, "Mi futuro será dorado" (My future will be golden). She's not talking about literal gold, but a future that is bright, precious, and valuable. She uses this beautiful word to contrast the priceless future she'll have with her love against the expensive material things she's ready to abandon, like her Rolls-Royce and fine china.
ROSALÍA is ready to get rid of everything. She sings about burning a Rolls-Royce to create her own light and throwing away her expensive Jimmy Choo shoes. She plans to let her porcelain break and give away her piano. Why? Because she has found something much more valuable. She says, "Ya no quiero perlas ni caviar / Tu amor será mi capital" [I don't want pearls or caviar anymore / Your love will be my capital]. For her, true wealth is love, and with it, she feels she has nothing left to lose.
This new perspective changes everything. The past doesn't scare her anymore; she imagines it sinking to the bottom of her wine glass. The simple act of drinking Sauvignon Blanc with the person she loves is all she needs. It's in this moment that she feels her future is secure and bright, singing "Sauvignon Blanc a tu lado / Mi futuro será dorado" [Sauvignon Blanc by your side / My future will be golden]. It's a song about choosing love and peace over luxury.