[FSL] Extraction of BOLD activation maps

[Troudi-Abir]

Dear all,
I'm a PhD student and I'm working on Functional MRI BOLD,
I'm a beginner researcher and I'm still learning on the manipulation of functional data with the FSL software, so i need your help if it's possible,
I want to extract the activation count maps for the language processing task, so
I collected the functional data, then I must work with FSL to prepare the activation maps, but I didn't really understand what are the instructions to follow to finally achieve a result as it is well illustrated in as shown in the screenshot below captured from the following article "Function in the human connectome: Task-fMRI and individual differences in behavior" (2013).
I would really appreciate any help from you.
Sincerely,