In my opinion starting with a spreadsheet is working backwards.
I start with the "big picture". What general area do I want to explore? Do I want to anchor out or stay at docks? What services do I want / need along the way. Those questions are best answered with guide books, internet searches and conversations with boaters experienced in the area of interest.
Once I have the season's big picture in mind if I want to plan in detail, which I rarely do, I have two general approaches.
On the laptop I'll use chart plotting software. Two apps I have are Coastal Explorer and OpenCPN. There are others.
On my tablet I use Navionics.
None of the three will take spreadsheet data and give me distances etc. All three will let me create routes and waypoints. Navionics will autoroute for me, but I don't like that.
Now it might be useful to employ a spreadsheet. Distance of each leg, estimated transit times, estimated fuel burn, time of critical tides and currents.
To be honest I rarely go to the effort of great detailed planning months ahead of time. A couple of days ahead on the cruise is all I want to do. This is recreational cruising at a leisurely pace for enjoyment. Not a grind making destinations on a schedule. Been there, done that in my career.