The only scource that can tell you which Laptop Motherboard you can upgrade with a newer or faster CPU soldered on is Toshiba Support: https://support.dynabook.com/
Dynabook seems to be the actual manufacturer of your laptop.
Need to remember the upgrade motherboard must be within your Toshiba's power and thermal ranges and that it will fit inside your laptop.
Personally I would just purchase a budget Laptop or possibly a Tablet depending on what you are using your laptop for.
