Is it possible to use AWS and Arduino Uno to upload data from Arduino to a website running on my localhost? I was wondering if it's possible to send data from my Arduino Uno (e.g. from the temperature sensor) to the Amazon Web Service RDS or anything there, which will then upload the data to a website on my localhost?

If yes, could someone give me guidance please?

I've been messing with this for a few weeks now, but I am just getting lost with linking it all up together.

Thanks.
No, it is not (easily) possible.

AWS has no access to your localhost - you are (most likely) behind a NAT router.

You could possibly open up port forwarding on your router and then ensure that AWS knows always what the IP address of your router is so it can connect (using some dynamic DNS service maybe).

However, that is not secure, and dynamic IP address assignments makes it a real pain. It opens up your computer to hacking from the internet.  A more secure method is to use AWS as the "central point" and have your computer go and fetch data from there rather than having it send data to your computer.