@wickeLine228 wrote:
I am working with "Mastering The STM32" book So this: https://www.carminenoviello.com/mastering-stm32/
Note that the author has a support forum: https://www.carminenoviello.com/mastering-stm32/forums/f/support-forum/
What version of CubeMX are you using?
Are you using a standalone CubeMX, or integrated within the CubeIDE ?
@wickeLine228 wrote:
cannot find the option as in the book to activate any timer using CubeMX.

That's for TIM6 - your chip, STM32F103C8T6, does not have a TIM6 !
See datasheet: https://www.st.com/resource/en/datasheet/stm32f103c8.pdf

That image from the book shows the configuration for a Basic Timer: as the name suggests, these have very few configuration options.
But this is the configuration for TIM1:

This is an "Advanced Control" Timer - so has a lot more options than just a simple 'Activate':

Here is an overview of the various types of timers available across the various STM32 families:
Application note AN4013: STM32 cross-series timer overview
https://www.st.com/resource/en/application_note/an4013-stm32-crossseries-timer-overview-stmicroelectronics.pdf