32-bit vs 64-bit

my research before exercism was all about 32-bit but this track is 64-bit. I’m interested in assembly for reverse engineering and malware analysis purposes, which I’m just starting to learn about as well.

any insight into what i should focus on is appreciated. I have good experiences with exercism and other languages, but everything I’ve come across thus far says i should focus on 32-bit. Are they really that different? As far as learning to read the code anyway?

I believe the main difference is the size of a byte/register. Aside from that, it should be fairly similar.

that’s what i was thinking, but wanted to check. thank you