how was your experience meeting your parents new spouse?

I’m suppose to be meeting my dads new spouse later this year and I haven’t met her yet since we live in different countries at the moment. My younger sister was upset with my dad about how the situation happened and does not want to meet her but we’re going on vacation all together so avoiding and not meeting is inevitable. I’m only 23 I don’t mind meeting her and getting to know her but I’m not that mature to know how to have a smooth first interaction like I’m super awkward and I obviously will say something if I feel like she’s taking advantage of my dad.