Q.Night Blooming Cerus Has Tall Spike With Roots Should I Do Any Thing
Should we just let it keep growing or cut and plant

Certified GKH Gardening Expert
Those are aerial roots to help the plant climb, and you don't need to do anything to it, unless the plant is too gangly and needs a trim. If you want to propagate some stems here is how:
https://www.gardeningknowhow.com/ornamental/cacti-succulents/night-blooming-cereus/night-blooming-cereus-cuttings.htm
https://www.gardeningknowhow.com/ornamental/cacti-succulents/night-blooming-cereus/night-blooming-cereus.htm