[Elecraft] bencher paddle

[Jesse & Nicky]

I am new to ham radio-jusr passed tech + morse in mar and will take general in jul.  I am bldg a k2/100 s/n 5437 a little slowly cause I am handicapped.  I am just getting ready for test & align pt 2.  Anyway, my ques is I just bought a bencher single lever paddle and instructions say follow directions on your electronic keyer for connection!!!
I don't have an electronic keyer.  I want to practice sending on a pc.  What else do I need to buy ???  an electronic keyer and serial cable ???

73 de Jesse W6JMM 

ps last time I used morse was 40 yrs ago with straight key--HeeHee