Upgrading a laptops CPU is next to impossible, you will be much better suited saving money and building a budget PC. It's also very possible that that upgrade is not going to be supported by the BIOS, and such will make it unusable. You'll also have to pick a model of the I3, because its even more likely that the sockets will not match.
TL;DR, No you're not going to be able to upgrade the CPU.