I’m new to the lifecycle of Lambda functions, so forgive my ignorance in advance!

I’m trying to understand how AWS Lambda can find and execute the specified handler in a Lambda function. Specifically, I would like to know:

I have a use case where I need to know the current size of queue in async invocation of AWS lambda, based on the queue size and few other data points my code has to decide how many more Lambda invocations to do.

I am uploading an ecr image to an aws lambda and invoking it.

When i migrating the lambda function, it is showing dotnet8 latest version.
AWS lambda function version dotnetcore 1.0 is deprecated, can i migrate it by dotnet8? If yes, then is it required in additional code changes?

I installed joblib through the procedure below, compressed it, and added it to the layer. But when I run the code, I keep getting this error. Could I possibly get some help?

I have created a simple console application using c#, that only has a console.writeline and created a container image out of it.
When launching the container from lambda, I do see output of console.writeline. But get a runtime.exiterror after that.