Bitcoin was not tradable (on exchanges) at the time. So, there is no answer to that question. In the early days, people were just sending it to each other, mining it using their computers or using faucets to claim it.
Bitcoin was originally worth next to nothing.
The transaction that first gave Bitcoin monetary value was in October 2009, when Finnish computer science student Martti Malmi, known online as Sirius, sold 5,050 coins for around $5.02, giving each Bitcoin a value of $0.0009 each.
I believe it only became tradable on exchanges in 2011.
For 2013 or above, I found this site which you can use: https://calendar.bitbo.io/if-i-bought/
For some reason that calculator didn't work for me. But hindsight is 2020 vision! I had the chance briefly before Bitcoin was long forgotten in my memory to buy Bitcoin in NY in 2010. I was about to put $20 into it but someone stopped me and on that day the price was .12 cents per bitcoin. IF I would have bought then today I might have had 167 coins and that translates to $15,030,000 at today's exchange rate. Safe to say I effed up lmao only $20 invested would net you 15 Mil today! Think about that, that's nuts.