In this current format, impossible (or way too complex) since you have all values in one column. It would be a lot easier to work with the values when you split each column into 4 - Name, start time, end time, time span (sum).
And split each row into 4 so each Name entry has its own line.
An example with the first week for Regan properly formatted:
https://docs.google.com/spreadsheets...it?usp=sharing
This relies heavily on data formatting and a few formulas. The name, start, end and time columns are formatted as time (HH:MM). Total time is formatted as [HH]:MM so the hours can go beyond 24. The summed-up times for each person are with the "sumif" formula that only adds up values of rows that contain a certain value/word. And the percentages are formatted as percentage (d'uh
)