My next question is how Private Key needed to spend coins. According to my understanding for transaction needed below steps:

1. A wants to send 10 coin to B
2. A make transaction example: from: A, to :B coint:10
3. A signs with its private Key: from: A, to :B coint:10, sign:qwertyasdfzxcv

So the result is B gets 10 coins on its public key (wallet address)

what is the usage of the private key to use this ? is this is transaction also getting encrypted by B public key (in this case only B's private key can be decrypted) if like that then noone can read transacrion to valite it ?

So, what is the technical usage of the private keys to use coins?

My next question is how Private Key needed to spend coins. According to my understanding for transaction needed below steps:

1. A wants to send 10 coin to B
2. A make transaction example: from: A, to :B coint:10
3. A signs with its private Key: from: A, to :B coint:10, sign:qwertyasdfzxcv

So the result is B gets 10 coins on its public key (wallet address) and sender Public Key is enough to verify sign of Sender.

what is the usage of the private key to use this ? is this is transaction also getting encrypted by B public key (in this case only B's private key can be decrypted) if like that then noone can read transacrion to valite it ?

So, what is the technical usage of the private keys to use coins?