OpenSSL can be tricky. You can try your distribution's package manager with the following commands:
sudo apt-get install openssl libssl-dev
The problem is that your distribution may have an old version of OpenSSL. If that is the case, you should obtain the OpenSSL libraries directly from https://www.openssl.org/source/. You will, of course, need to build OpenSSL before it can be used. Building OpenSSL is not easy, but instructions are provided in the INSTALL file included with the OpenSSL source code. Note that its build system requires that you have Perl installed.