Data Types, Operators and Expressions: Variables and constants - declarations - arithmetic and logical operators – Assignment operator – Input/Output. Control Flow: Statements and blocks – if-else, switch, while, for and do-while statements – break and continue – goto and labels.
Functions and Program structure: Basics of functions, Parameter passing – scope rules – recursion
Aggregate data types: Single and multidimensional arrays, structures and unions – Pointers to arrays and structures – passing arrays and pointers as arguments to functions.
NOTE: Here are some websites that are almost equivalent to “C Programming for Dummies”: GeeksforGeeks, Stack Overflow.
"GeeksforGeeks also provides tutorials!"
HackerRank is also a platform that you can use to practice!
NOTE: You can find a lot of video lectures on C programming, the attached playlist has pretty much everything you need.