send-to-vterm.el

(defvar my-vterm-command nil)
(defun my-vterm-execute-region-or-current-line (&optional arg)
  "Execute a command in vterm, pass variable or ask for it"
  (interactive "p")
  (require 'vterm)
  (eval-when-compile (require 'subr-x))
  (let ((command (or arg (read-string "Enter a command: "))))
    (let ((buf (current-buffer)))
      (unless (get-buffer vterm-buffer-name)
        (vterm))
      (display-buffer vterm-buffer-name t)
      (switch-to-buffer-other-window vterm-buffer-name)
      (vterm--goto-line -1)
      (vterm-send-string "")
      (vterm-send-string command)
      (vterm-send-return)
      (switch-to-buffer-other-window buf))))
(my-vterm-execute-region-or-current-line "ls")