Need to get better gaming preformance out of a laptop, but can't get a new laptop?

So, my parents got me a laptop (Toshiba Sattelite C55-C5268) and it's okay in gaming. Not the best (Planetside 2 needs 800x600 to get 30fps) But I still get like 60 fps in games like minecraft. I'm not allowed to get a new laptop, but I may do whatever I want to this one. It seems upgrading laptops are really hard but in some cases possible (If this model can do that please let me know) but I've also heard of a thing called external components. Is it possible for me to plug in like a better proccessor or graphics card without me having to worry about it fitting?

Most laptops have a video chip on motherboard. No way to change.
You can modify a laptop to get more video power:
Take its backside apart and remove the Wi-Fi card from the mini-PCIe slot. Plug in an extending cable to an external PCIe slot from a kit. Get a desktop PSU and GPU card. Hook up to external monitor. Costs $300 to $whatever, depending on card and monitor.

They are easily overheated and ruined.