Hi, Sing-
The problem is your R version: you have R-4.0, which is noted in the AFNI system check output here:
R version : R version 4.0.2 (2020-06-22) -- "Taking Off Again"
At the moment, on a Mac you need R-3.6.*
The correct version of R is specified as part of the install instructions here-- the link at the top of this section gets you the correct version:
[
afni.nimh.nih.gov]
...and/or the Mac App installer should also get you the right R version (but since you are mostly setup already, I would probably just get the R-3.6.* directly, above).
Please note that there are some other steps noted in the system check output in the bottom section to do to complete your install-- mostly copy+pasting things into the terminal.
--pt