What first date advice do you have and how do I choose which girl to be exclusive with?

I know I posted about having a foreign name, but I asked out a lot of girls who were born in the USA.

I thought being a foreign born Indian would turn them off, but they surprisingly said yes. One girl is East Asian American, one girl is White, one is Indian American and one is Mexican American.

Should i research on their cultures to avoid culture clashes or avoid offending them? How do I be flirty but not creepy? And how would I make myself a better person to date than other guys who approach them?

how do I flirt with them on dates? And how do I choose between one of 4 of them at the end, without them fighting over me or going after me and calling me a cheater? Or how can I encourage all 4 girls to be polyamorous?