Footer auto update & Header Logo Size

Hi, quick questions:

1. How do we generate auto update on the footer year?
2. What is the ideal size for the Header logo? for vector file .svg, I tried different sizes but couldn’t seem to get the right size it always came out too big. I currently am using png file with dimension of 256 x 50px and it works fine (its too small and pixelated tho) thus I wanted to upload svg instead but when svg is uploaded with the same size (256 x 50px, it came out too big)