The "Percentage of conversion to selected statuses" field (renamed by you to Conversion) shows:
How many times the processes that you filtered here:
https://prnt.sc/w9svow (if you did not filter the creation date, then the processes for the last month, about 30 days are taken) went to the selected statuses
https://prnt.sc/w9svgg . Either way, they are closed or open. There is a process created at a certain time and it has moved to a certain status, so we consider it as a conversion. Then we take the number of such processes and divide by the number of all processes for this period and multiply by 100.
Those. if you had 10 processes and they went to the stages selected in the settings 5 times, then the conversion is 50%