I am just wondering what are the methods which can hide all the transactions and also able to validate transactions in an block chain?

I am new to block chain and was looking at how block chain work mainly proof of stake based . They check validity by going through all the transactions which is something concerning as everyone can see the transactions. So what are ways to hide all transactions and also make everyone able to check validity of new block. This question is not only for block chain relm but also for cryptography.