How can I get telnet on my macbook pro with High Sierra
I searched through Apple support forums and found an answer that I believe will help others reinstall ftp and telnet on Mac High Sierra.

Navigate to www.gnu.org/software/inetutils/
Click on the HTTP download link for "Inetutils"
Download "inetutils-1.9.4.tar.gz"
tar zxvf inetutils-1.9.4.tar.gz

Direct ftp site -> http://ftp.gnu.org/gnu/inetutils/

cd inetutils-1.9.4
./configure
make
sudo make install


telnet x.x.x.x port

I found the answer at this forum
https://forums.developer.apple.com/thread/79056