Curious about the Math that makes Bitcoin/Blockchain work ! Any good resources to learn it?

[Bitcoin]

Curious about the Math that makes Bitcoin/Blockchain work ! Any good resources to learn it?

A bit of a background about me ; Computer Engineer but during my studies i didn't dive too deep into the maths , especially the maths that makes the blockchain and cryptography work

looking for advice from any senior or experienced researchers or practitioners in this field to give me some advice and point me towards the correct direction

E.g one example of the type of math i am looking for = so you know how the term Elliptic Curve Cryptography (ECDSA) keeps coming up all the time ?

i know very little about how exactly are the private keys extracted from an elliptic curve - i'd like to understand how exactly are we able to derive something as vital as a wallet private key from an elliptic curve .. how does this work to help Bitcoin or any blockchain become secure ? That's what i want to understand through the math !

if you can outline exactly which math topics i need to revise and learn - i would be thankful !

P.S : suggestions for any useful and relevant online courses are most welcome !

Source: Curious about the Math that makes Bitcoin/Blockchain work ! Any good resources to learn it?