9max 0.5USD, 99

I need opinions on both decisions - to simply call preflop and check/raise flop.

My thoughts were:
Preflop, if I were on 10bb, id have went all in, but on 12bb I decided 1.5bb call was good value to check maybe I can catch a 9 on flop or the flop is low cards. I liked the flop, checked because I was out of position and didn't like the possibility of anyone having a T. I was planning on folding if anyone raises at least 50% or goes all in.

UTF+1 checked (took it as weakness because he min raised pre flop so I put him on low A's or K's, possibly QJ KJ ), CO bet very small, which looked as a sign of weakness too.

I guess shove is better since you are underdog with 99 against 3 opponents.
I would fold OTF with 3 ppl to act behind

You need to invest almost 1/6 of your stack to call here and the UTG+1 player seem fishy. So I would push here for sure and then you don’t have any difficult post-flop decisions as well.

Cheers,
SDK1987