I am trying to make pretty urls using rewrite rules but they are not working

1.

https://example.com/s1/video.mp4 should be rewrite to https://example.com/file/server/video.mp4

location = /s1/(.*)$ {
rewrite ^/s1/(.*) /file/server/$1 permanent;
}

2.

https://example.com/view/video5353 should be rewrite to https://example.com/view.php?id=video5353