monthly Subscription box page in my shopify store

i have an online shopify store. and i would like to add a section for a subscription monthly flat rate box. where customer will choose 1 item per section. until they build the box that will come to them monthly. It will be 3 boxes at 3 different prices. one with more items than the other one • i need help setting it up. i can't find an app that will allow customer to build their own box from the choices i give them. The only way i could thought how to do it is doing the subscription box in another platform like crateful the problem will be that customer will have to use 2 separte account . one for my store and another for the subscription box and i dont what that . Example: What blades would you like? They will choose the one they like. What after shave would you like? They will choose their after shave, Shaving Cream ect ect... example of website will be [login to view URL] [login to view URL] [login to view URL] • Soon as possible? week or so.. PS. I will be using the theme named ''Showtime'' on shopify not the one that is currently on my website