You should learn to write this simple stuff... not just exploit other users' willines.
(vl-load-com)
(defun c:FilletProcess ( / o1 p1 i1 o2 p2 i2 ao ai r w)
(and (setq o1 (entsel "\nSpecify 1st side outer: "))
(setq p1 (vlax-curve-getclosestpointto (car o1) (trans (cadr o1) 1 0)))
(setq i1 (entsel "\nSpecify 1st side inner: "))
(setq p2 (vlax-curve-getclosestpointto (car i1) p1 T))
(setq i2 (entsel "\nSpecify 2nd side inner: "))
(setq o2 (entsel "\nSpecify 2nd side outer: "))
(setq r (getvar 'filletrad))
(setq w (distance p1 p2))
(setvar 'filletrad (* 1.25 w))
(vl-cmdf "_.fillet" o1 o2)
(setq ao (entlast))
(setvar 'filletrad (* 0.25 w))
(vl-cmdf "_.fillet" i1 i2)
(setq ai (entlast))
(entmake (list '(0 . "LINE") (cons 10 (vlax-curve-getstartpoint ao)) (cons 11 (vlax-curve-getstartpoint ai))))
(entmake (list '(0 . "LINE") (cons 10 (vlax-curve-getendpoint ao)) (cons 11 (vlax-curve-getendpoint ai))))
(setvar 'filletrad r)
)
(princ)
)