"Featured Image" Changes

Hello!

I have several questions.

1.) Is there anyway to add a custom URL/link to the “Featured Image” in a post?
2.) Is there a way to make it so the Featured Image always shows up as the same size on every post? For example, say I want it, regardless of the actual size of the image in the media library, to resize to something like 270/76.
3.) How can I adjust where the Featured Image is shown in a post? I would like it to show the image right after the date but before the text.

Thanks!