What tech stack would be best to host an Angular application?

I've recently started working on an app using Angular, and the frontend portion of it is fine. I am now getting to the point of no longer just mocking my requests but setting up the backend/api architecture.

Now, I have done some AWS certifications so that seemed like the obvious choice. I tried out Amplify for a bit but wasn't a huge fan of not exactly having 100% control of what happens behind the scenes. Also it made use of DynamoDB which doesn't suit my use case as I would prefer a relational database. I stsrted trying out RDS but it seems to be very expensive even though I have barely used it. I like the fact that I'm able to host in S3 and could use cloudfront to make it accessible, but I need to find a better/cheaper database.

Any suggestions?