I have one app and the first year is coming up. I received the email reminder that I have 30 days before my IOS Distribution certificate expires. I can't figure out how to renew the certificate through a desktop computer. When I originally signed up for a developer account and added my app it was from a desktop (I don't own a Mac). However, I can't remember how I generated the original certificate.  Can someone help me out? Thanks

So new I may not know the correct terminology, thanks for your patience. I hired a developer to create an app. He coded in React Native. He does not have a Mac so I am talking with another developer who has one and says he needs access to my account (individual account) to generate a signing certificate to be able to upload it. I tried giving him access as a "developer" but he says he needs "account" assignment. I do not want to give that level of access. I borrowed a Mac from a friend and am wondering if there is a way that I can generate whatever certificate is needed, send it to him so he can upload app under developer access? If so, which certificate option do I need to get? When I asked the original coder what language he used he gave this response.. react native just run command react build ios but he need have macbook My next question is, can I do that from the Mac I just borrowed? And would that process be via X code? Thank you for any advice.