Hiya welcome to the forums,
Maybe I'm not quite understanding. Is each date column (Live Class Tues or HW Due Mon) derived from the initial "Important Dates" column?
In Airtable, each column is called a field. Fields are treated to hold the same type of information. This means we can set a field to have a formula deriving from the first date, but all cells in that field MUST follow that formula. I can help you find the right formulas if this is what you intend.
If you want each cell to have a different formula depending on the event type then there's a little bit more to build.
If you could manually create a few examples in Airtable and provide screenshots of it that'd help a lot! With that we could compare it to your Sheets screenshot to see how you want your data created and could try to suggest formulas that might help