Do not attempt to upgrade soldered RAM.

No. Soldered RAM is permanently attached to the motherboard. You cannot upgrade it yourself without specialized equipment and risk of destroying the board.

If you try to desolder and replace the RAM chips, you will almost certainly damage the laptop. The manufacturer will see the tampering and immediately void your warranty. Even if you somehow pull it off, they won’t cover a defect on a component you modified — that’s not what a defect policy is for.

If you want the ability to upgrade RAM later, buy a laptop with SODIMM slots. Soldered RAM is a trade-off for thinness and lower power consumption. Accept that or choose a different machine.