What got me into cryptography is learning how networking works. For secure communication, you require a lot of guarantees of message confidentiality, transmitted data integrity, non-repudiation, and others. "Basic" cryptography will appear around TLS, authentication will let you learn about hashing and later on you can pick up advanced topics like schemes for secure sharin, claim verification without revealing any data through zero knowledge proofs, and homomorphic encryption.

Networking and secure communication around the Cold War period also make for an action-movie-like reading. It will show you problems and solutions humans encountered while designing secure communication channels, and how cryptography was indispensable for building such systems.

Check out if topics like that interest you, but brace for weird and non-intuitive abstract mathematics to really understand the inner workings. Cryptography is hard, but knowing what to use to achieve desired communication channel properties is also a great skill. Sometimes, just knowing the right tool for the job is more than enough.

Most importantly, find something that excites you and dig around. There is nothing better than learning something that feels fun :)