AWS Lambda is a service used for serverless computing. i.e cloud provider runs the server, and dynamically manages the allocation of machine resources.
S3 is a storage service but can be used to host static websites. So to deploy Angular frontend use Amazon S3.
To show image processing results -
For backend image processing you can use Lambda and AWS API Gateway along with S3. For this recommended you can use the API Backend to get an Signed URL or AWS STS in Lambda to get temporary access to Amazon S3 Bucket to Upload the image directly to S3 from Angular App.
After Uploading the image to S3 you can setup an event driven workflow by using Amazon S3 triggers to invoke an Lambda function to perform the image processing and save the process image back to S3