Defaulter's sentence experience?

I'm coming back after defaulting because my family thought we could get citizenship somewhere else, but it didn't work out. I was wondering what the process of defaulter's is like? Anyone have experience, or have friends who have experience? Namely:

• What's it like if I'm coming in from the airport? Do I get detained? If so, do I have an opportunity to send my belongings somewhere?
• If I'm jailed, is it with other hard criminals?
• What's the overall jail experience like?
• Would the sentence be before or after NS?
• Would my NS experience be inhibited due to my default? Would I be held back from promotions, punished worse, etc.? I know the sergeants or whoever might not ever say it that explicitly, but has anyone experienced it?
• Are there things I can prepare for before going back? I've watched a couple of content creators on NS, read through the official website; just wondering if there's some sort of must do's or don'ts people who've grown up in Singapore know that I don't?

Thank you!