"Eu posso dormir em qualquer cama."

Translation: I can sleep on any bed.

[Agfay]

preposition in can also be good here.

[GreengoStarr]

Not only can it be used, it should. On would signify on top of everything - sheets, blankets, etc.

[nato119]

"Qualquer" here can also be translated "either" right? I reported