I have recently started using a Multivendor Marketplace app on my shopify store but I am struggling with the shipping part. I would like to generate a few shipping options from my side manually that my sellers can choose from but now the support at the Multivendor marketplace app is telling me that I need to activate the third-party carrier calculated shipping app in shopify in order for me to do this but I dont think they understand me correctly. Is there a way that I can generate the shipping fees manually on shopify’s side so that it shows up on my website? Upgrading my shopify plan is not an option at this moment.