So can we can't solder another graphic card by removing soldering of old GPU
If you had the knowledge and skill required to be able to do this, you wouldn't have to ask if it can be done. The equipment needed to just to remove and replace a BGA chip would cost more than the laptop. For most intents and purposes BGA CPUs and GPUs are not upgradable and not just because of the equipment and skill needed but because of other concerns such as bios and cooling support.
So can we can't solder another graphic card by removing soldering of old GPU
If you had the knowledge and skill required to be able to do this, you wouldn't have to ask if it can be done. The equipment needed to just to remove and replace a BGA chip would cost more than the laptop. For most intents and purposes BGA CPUs and GPUs are not upgradable and not just because of the equipment and skill needed but because of other concerns such as bios and cooling support.