Hi, I'm very bad making loops

I tried to export and generate variables in this way. I have to do that segment of code but for several excel files.
The problem is that I don't know how to replicate because matrix selecting which cells to import change with each file.

Below, its shown an example of my code, but, as you noted, within cellra, numbers of matrix changes. I have like 30 excel files more or less, for that reason I'd like to accelerate the process.
It would be very nice some kind of strategy.
Thanks.

Code:
clear all
import excel "INDECOPI ENERO  2019 - PARTE 1.xlsx", sheet("LIQ_EVP_DMAY_CCA_CCE") cellra(A5:L99235) firstrow
gen fecha=date(FECHADEREGISTRO ,"DMY")
format fecha %td
drop FECHADEREGISTRO
rename fecha FECHADEREGISTRO
destring CODIGOOSINERG, replace
saveold INDECOPI_Enero_2019_1_grifos,replace

clear all
import excel "INDECOPI ENERO  2019 - PARTE 1.xlsx", sheet("GLP_EVP_PEGL_LVGL_COM_PROD_IMP") cellra(A5:L14651) firstrow
gen fecha=date(FECHADEREGISTRO ,"DMY")
format fecha %td
drop FECHADEREGISTRO
rename fecha FECHADEREGISTRO
destring CODIGOOSINERG, replace
saveold INDECOPI_Enero_2019_2_grifos,replace

clear all
use INDECOPI_Enero_2019_1_grifos, clear
append using INDECOPI_Enero_2019_2_grifos
saveold INDECOPI_Enero_2019_parte1_grifos,replace