How to create value in dropdown from input user
Welcome to the forum @pelarnut01
The help tab for the dropdown node tells you how to do that by feeding in an array of options in
msg.options. If you don't understand how to do that then I suggest you start by spending an hour watching the Node-red Essentials videos linked from the node-red docs, and then reading carefully the docs page Working with Messages. If you are still stuck then come back here and explain exactly which part of the problem you are having difficulty with.