That Tools > Partition Scheme menu is a custom board option, meaning it is defined on a per-board basis. For some reason, certain of the ESP32 boards have this custom board option, but not all of them. So if you were to select something like Tools > Board > Robot Zero One, you would then see that menu appear.
At a glance, it seems like the ESP32 boards platform maintainers might be taking the approach that contributors to the project have to add this option in for each individual board, so it's just a matter of whether some member of the community wanted that feature badly enough to do the work and submit a pull request: https://github.com/espressif/arduino-esp32/pulls?page=1&q=is%3Apr+partition+is%3Aclosed
The ESP32 Dev Module in the Board Manager has that option, so maybe you could use that to program the ESP32 instead, but i am not too sure if it supports your board as the firmware / hardware might be different