What swimwear should I use?

Hello! I have never gone swimming with my NF before, but we are going on vacation in a month, and I know i will be wearing swimwear around them. Typically, I dress relatively modestly at work (may sometimes wear a crop top) but the family has never said anything about the way I dress. However, now that we are going on vacation and i will be at the pool with the kids, I'm wondering what is or isn't appropriate in terms of swimwear. Ideally, I would like to have at least two bathing suits that I can wear other times in my life. I don't see myself using a one piece, but maybe if it is very cute. Would it be appropriate to wear a decently covering bikini top with high waisted bottoms? Something like this: https://www.asos.com/us/asos-design/asos-design-mix-and-match-crinkle-skinny-scoop-crop-bikini-top-in-coral/prd/201943180?ctaref=we+recommend+grid_5&featureref1=we+recommend+pers

Cleavage is not an issue for me, seeing as i have barely anything to show. Or should I just buy a cheap one piece or tankini?