Bitcoin was "invented" by a person or group of people with the name "Satoshi Nakamoto". Does anyone really know who he is? While there have been countless articles and investigations to find out the truth about who he (or they are), there isn't enough evidence to date. Is it important? Not at all. Satoshi designed the entire Bitcoin system in an "open manner" - meaning that the code is available for everyone to see and check, so there are no hidden secrets and no influence from the creator. As time went on, lots of people started working on these codes so it was very different from Satoshi's original design.
It is important to remember that there is a misconception about Satoshi that Satoshi created Bitcoin on his own. Like other major breakthroughs in science, Satoshi's creations were built by the hands of many people. In recent decades, many distinguished experts, technicians, and mathematicians have been involved in research on cryptography, systems, and more. Satoshi managed to summarize all this work into one coherent and clear plan and then implemented the plan. If you read the Satoshi Whitepaper, you will read references to all the discoveries that led to his success in this work.