How useful are vacuum cleaners in Indian households?

Thanks to COVID-19, we can't allow our regular house help. She used to go in this sequence:

• Dusting - With a small cloth, dust-off all surfaces/items like vase, TV, etc.

• Brooming the floor.

• Wet-mopping the floor.

Now my mom is a real stickler for cleanliness. So her questions with a vacuum cleaner are:

• Can I use it for dusting?

• How good is the dry cleaning of the floor as compared to a broom?

• I am zeroing on this one. Does it look okay?

I just don't want to buy one and let it collect dust in the closet.

Update No carpets. Only marble floors. No pets.