Discussion on: I need some Lambda Function/ Netlify Function stuff.

You can test on a local machine using the netlify cli. Specify your dev command in your netlify.toml file. Then type
Netlify dev

This spins up your dev command (eg. Npm run dev), and your function lambdas. You can access them both via localhost:8888
Your functions will be accessed via
Localhost:8888/.netlify/functions

You can use Postman to test.

Netlify Dev