I would like to know more about drone which can handle more weight .. what are key things we should consider
These drones are all about the same.
The more you want to lift, the more power you need.
The more power you need means the battery goes flat sooner.
When the battery is flat, you are grounded.
Basically you need to balance the drone power with the payload that you want to lift and then figure out how far or how long you want to fly.
No matter which option you choose, gravity always wins in the end.