What is the problem?
I thought I read that there would be one button fro PLA, ABS, PTEG, etc... th set both the nozzle and bed temperatures?
What did you already try to solve it?
I looked on every page and in every Settings page.
Additional information about your setup
OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible
Octoprint 1.4.2 Image 0.17
MBP 2015 32GB RAM, 1TB SSD
Mac OS x 10.14.6 Mojave