The game as downloaded from this site should be free of errors on start. If on the off chance you added any mods or bugfixes, then it would help me to know what has been changed.
If you are using the vanilla game, then the problem is likely that the game's user folders were altered either by you or your system. The default location for these folders is "C:\Users\YOUR_USER_NAME\AppData\Roaming\Strive". If you are using the itch.io launcher, then it may be interfering with the folder placement. https://itch.io/t/586531/bug-playing-strive-with-itchio-launcher (The Discord bugfix described in that issue will probably not resolve this issue.)
Otherwise, your "progressdata" file has incorrect data. It should be located at "C:\Users\YOUR_USER_NAME\AppData\Roaming\Strive\progressdata" and either renaming it or deleting it will cause a new one to be created.