Arduino IDE 2:1.0.5 on Raspberry Pi...HELP

i am having a problem with the Arduino IDE on my Raspberry Pi’s. It is running 2:1.0.5. Unlike Arduino IDE 1.6.7 on my win 10 tablet, when I goto file>preferences> I cannot find the Addition Boards Manager space to enter a URL. Is there a sudo apt-get type file to add new boards? Google, digistump nor on the Arduino site could I find answer. I just want to hook up my digispark attiny85 via UsB (not GPIO).
How do I add more board packages to me Raspberry Pi arduino IDE?

here’s what my tablet has my Pi doesn’t.

now here is my Pi’s:

I re-installed the IDE. This time not through apt-get nor through the add/remove software option under Pi GUIs preferences.
The following link has the basic instructions of download link, extract & install.

This IDE has the "Additional Boards Manager URLs " area. It is version 1.8.3