I think there is a typo in the following two sections:

https://cryptobook.nakov.com/encryption-symmetric-and-asymmetric.html?q=#private-keys

Message encryption and signing is done by a private key.

Shouldn't this be "Message decryption and signing is done by a private key." ?

https://cryptobook.nakov.com/encryption-symmetric-and-asymmetric.html?q=#public-keys

Message decryption and signature verification is done by the public key.

And shouldn't this be "Message encryption and signature verification is done by the public key." ?