In your initialization file, bind the Transient casual-csv-tmenu to your key binding of preference.
(keymap-set csv-mode-map "M-m" #'casual-csv-tmenu)
While not required, the following configuration is recommended for working with CSV files.
;; disable line wrap
(add-hook 'csv-mode-hook
(lambda ()
(visual-line-mode -1)
(toggle-truncate-lines 1)))
;; auto detect separator
(add-hook 'csv-mode-hook #'csv-guess-set-separator)
;; turn on field alignment
(add-hook 'csv-mode-hook #'csv-align-mode)