Most of the time, 所有and一切 are the same. =>Both of them can be used as an adjective or noun, which has the same meaning as "all" ,"everything" or "all the things"; =>Both of them can be used as the subject or the object of a sentence.
一切都是有可能的。（Everything is possible.) 所有的灯都被打开了。（All the lights were turned on.) 感谢你为我做的一切。（Thank you for all the things that you've done for me.)