C is a good language for learning this. Just don't use your resulting programs on untrusted input; you _will_ make mistakes that _will_ result in security flaws.

Once you've shot yourself in the foot enough times (everybody does), you'll be able to come back to Rust and understand what it's doing. Many design choices in Rust won't make any sense until you've experienced the problems they solve.

For example, lifetimes in Rust make explicit what you would normally need to track implicitly in C.