Issues with partitions on SSD - MacBook Air

I was on big sur but decided to go back to Catalina through recovery however it didn’t work.

i then erased my ssd and named it macintosh hd but can’t help but notice it says containerdisk 3.. why not 1? There’s no 1 there, there’s a 2 under I think it’s called base system? Is it still gonna work properly or does something need setting properly? Thanks