I think Alina Baraz has a really soothing voice, I listen to her songs to help me to fall asleep. She also sounds a bit like Lana Del Rey. My favorites by her are, Pretty Thoughts, Can I, Make You Feel, Fantasy, and Show Me. Just search up her name and you'll find her music. P.S. She makes her music with Galimatias. Hope I could help you!
I love lana del rey so much. Similar artists are: Banks, Fiona Apple, Broods, Daughter, Fka Twigs, HANA, Lights, Say Lou Lou, and most closely, Nicole Dollanganger. Her voice is so ethereal and calm, it's like a dream.
Go find a 70s band called Renaissance. They are kind of a progressive band like Yes or Pink Floyd, but with an incredible vocalist named Annie Haslam. She has a five octave range, and wrote much of the music and lyrics. See if you can find the live versions of "Ashes Are Burning" or "The Song of Scheherazade". Both are more than 20 minutes long, and fantastic to listen to with the lights low (or off), and with a glass of wine. If that doesn't qualify as 'dreamy', then I don't know what does.
Zella Day, Halsey, Banks (Highly Recommend as well as Florence and the Machine), The 1975, Dua Lipa ( Has the same manager as Lana and also highly recommend), Carly Rae Jepsen's newer album, Marina and the Diamonds, Kiiara, and Ellie Goulding.
Everyone here is suggesting Melanie Martinez and yeah I think she's similar but I noticed no one has mentioned Halsey??? She's almost exactly like Lana, her new album Badlands is awesome, listen to the songs New Americana and Colors and you'll know what I mean.
These artists don't sound like Lana Del Rey, but they sound dreamy: Echo Lake, Beach House, Cocteau Twins, Slowdive, My Bloody Valentine