I sent my token to dead address(0x000000000000000000000000000000000000dead) At first I was trying to burn all my token so I sent the token to the dead address using meta mask. Now I can see the my token(https://bscscan.com/address/0x0083a5a7e25e0Ee5b94685091eb8d0A32DfF11D4)'s total supply isn't reduced. And the dead address is the holder of the token. How can I fix this out? Actually I want to remove all tokens minted from my tokne.
I'm afraid you have misunderstood the concept of burning coins. Burning does not destroy coins. It sends them to an address/wallet/account that can only receive but cannot send (or spend) them, making them effectively lost forever as this is recorded in the immutable ledger.
This means that the supply of tokens in circulation (those tokens that can still be used to make transactions) is reduced, but not the total supply. So actually, everything that happened in your case is completely expected.
Here is one among many internet resources that explains the concept of burning coins: https://www.investopedia.com/tech/cryptocurrency-burning-can-it-manage-inflation/