New to serverless - can someone clarify this please

Hi, I’ve been at it for 3 or 4 days, I’m exhausted and frustrated. While a simple deployment is easy, making a real application looks a little bit of a pain.
Is there a way to create a simple Node.js app with Express.js and link my HTTP API created already in AWS + my already created DynamoDB?

In other words, I want to manage my services online using the interface but develop my Lambda offline using serverless. How can I do this? Every time I try it creates a 1000 resources in Cloudformation and also they are new, not the ones I created.

Please some help, this my current serverless.yml:

service: planner-api
# app and org for use with
app: planner-api
org: username

# You can pin your service to only deploy with a specific Serverless version
frameworkVersion: '2'

  name: aws
  runtime: nodejs12.x
  lambdaHashingVersion: 20201221

  stage: v1
  region: us-east-1
  stackName: planner # Use a custom name for the CloudFormation stack

    name: test15
    handler: handler.hello
      - httpApi:
          path: /users/create
          method: get

This whole thread is quite misleading. The right conclusion, which is also the one supported by the article you post, is: FaaS is not suited for all types of applications.

One very poorly suited application the article mentions is relational databases: you can’t really build them on top of snaptube vidmate lambda.