Is it okay to still talk to other guys after a first date with a guy I’m getting to know?

I have a friend that thinks I should only see, date or speak to one guy at a time because what if another seen us in public or what if he somehow knows someone else that’s talking to me etc

but on the other hand getting to know others helps me not get too overly emotionally invested in the situation with one particular guy, it helps limit the disappointment if they find somewhere else or lose interest

Is it okay to still talk to other guys after a first date with a guy I’m getting to know?
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