It's probably the main fuse.  Make sure the battery is connected to the
cables with the correct polarity.  The minus (-) lead is grounded to the
chassis of the car. Accidental polarity reversal can cause a lot of damage.
It is easy to get the wrong jumper cable connectors on the poles of a dead
battery.  If the main fuse is blown, the diodes in the alternator could be
shorted and the ECU blown.

Make sure the battery is disconnected. Replace the main fuse.  Check the
resistance using an ohm-meter from either connection on the main fuse to
ground.  If it reads a dead short, disconnect the alternator and try again.
If the resistance is a high reading you are okay. Reconnect the battery and
turn the key to the Accessory position and see if the radio works.  If so,
try to start. If the car does not start you have a damaged ECU or coil pack.

Good luck!