Customize the blogpage layout

I just wanted to check how to further customize the layout/content of the blog page?

Some examples I’d like to accomplish:

– Adding a full screen image and logo above the post feed?
– Being able to specify which post/s (not necessarily the latest) to pin to the top?
– How to customize how posts are shown? (adding word counts, excerpts, etc).

Let me know if I need to create multiple questions for this. Forgive me if I overlooked the answers elsewhere in the forum.

Many thanks!