@Jean David Ruvini Thanks for reaching out. According to the documentation https://learn.microsoft.com/en-us/azure/azure-functions/functions-how-to-use-azure-function-app-settings?tabs=azure-portal%2Cto-premium#plan-migration, migration of function apps from a consumption plan to a premium plan is not supported for Linux function apps.
Given this limitation, you will need to create a new function app in the desired premium plan and then migrate your code and settings manually.
do let me know incase of further queries, I would be happy to assist you.