Car won’t turn on even with jumper cables hooked up?

Could be the security system. Read the owners manual to see what step to take after changing a battery- dead is like disconnecting it in some cases. Charge the battery up fully with a battery charger.

Leave the cables hooked up for twenty to thirty minutes. It takes time to charge. Also, the engine of the car from whom you are drawing power should be running during this time.
(Make sure your lights are turned off.)
Then with both your newly charged battery plus the donor car's power, you should be able to start the engine.

Even then, your battery will not be fully charged. You may wish to leave your car running (idling) for an hour to continue charging.

The fusible like burned out

Clean the battery cables.

Chances are the clips are not making good contact. Also, clean the battery terminals. I think some cars have a security issue but can't fill you in on that. I think disconnecting the battery will clear it.

Charge the battery and see if that works. It may have failed.

Remove the battery and get it charged and load tested. Install a charged battery or a new battery. Key ON. Do you have lights in the dash? No? Turn the headlights on. No headlights, check for a bad main fuse. Check if power is coming to the distribution box. Headlights on, check check for bad ignition and cluster fuse. Check for power at the ignition switch.

If the dash is on, try to start.

How long did you leave them on? Did you make sure the other car was running?

Did you check the voltage?

Possible you fried the battery, but may just need a few minutes.

Simple, set switch to 'magneto mode' and turn over with the hand crank provided by the Landrover company for the short Safari models , be careful of backfire. about like the Model A Fords with the secondary Magnetoes. Simp[e to do with the car/trucks meant for colonial use. Your car is NOT a Landrover Short Safari?? Then what it actually?

No current is passing through the dead battery, so you don't have a closed electrical circuit.