Firstly smoke has many causes
Fried pistons rings
Maybe just the seals are gone
Take it to a proper educated mechanic to find the cause
Secodly you can swap and engine but a swift one in alto is not going to be easy. I dont think there is enough space in alto for a swift engine and even if there was you would need custom mounts and custom brackets fabricated to your specs which is not easy. So dont even think about swapping a swift engine. Better option would be a newer alto engine in your car.
And 1 week would only be possible if the same engine was swapped. Anything different it will take time