The center of any imperative programming language is control structures. Although Perl is not purely an imperative programming language, it has ancestors that are very much imperative in nature, and thus Perl has inherited those same control structures. It also has added a few of its own.
As you begin to learn about Perl's control structures, realize that a good number of them are syntactic sugar. You can survive using only a subset of all the control structures that are available in Perl. You should use those with which you are comfortable. Obey the "hubris" of Perl, and write code that is readable. But, beyond that, do not use any control structures that you do not think you need.