My company purchase a car on bank loan. I have shown as a fixed asset of the company and credit the bank loan account.
BUt the car got accident and total loss.
BUt the insurance has paid the after deducting the depreciation amount.
Please show me the entry in the ledger to nullify the fixed account.

The effect is that the insurance company has purchased the car (what's left of it, anyway) from you. The price they paid you for the car is simply the amount of cash they gave you to settle the claim. Thus, treat this in the same manner as a sale.

Remove both the fixed asset amount, and the accumulated depreciation amount, from your books with a Credit to the former and a Debit to the latter. (The difference in these two amounts is, of course, your 'net book value' in the car.)

You'll also Debit Cash for the amount received from the insurance company. Finally, you'll either Debit a loss account, or Credit a gain account, for the difference between the car's 'net book value' and the insurance proceeds.

With those four items you'll have a balanced JE. Cheers!