best way to get from Nice to Lake Como Saturday, March 28th

From Nice, take a train to Ventimiglia. Transfer to a train to Milano Centrale and then transfer to a local Trenord train to Varenna-Esino. Buy your Ventimiglia-Milan-Varenna-Esino tix at www.Trenitalia.com

On the Trenitalia website, look for the direct trains from Ventimiglia to Milan at 9:10, 10:59, 15:10, etc. The others require changes.
The Nice-Ventimiglia train is a local commuter train that runs every 20 minutes.

You can find trains on www.bahn.de
That site has all the schedules.

Tickets are a bit tricky, as SNCF is basically in a cold war with Trenitalia. But just buy Ventimiglia - Varenna (or wherever on Lake Como you are headed) from Trenitalia, and buy the local Nice - Ventimiglia ticket at the station.

rome2rio is another site that maps out options pretty well, better than google maps for public/private transit connections. And if you are staying somewhere along the lake, the ferry becomes an option for the final leg (I've taken it).

Be aware if you depart at noon the frequency of the train from Nice has dropped (and night service as well sun->thur). They are also doing work on the line this year, so that hopefully trains will increase in frequency and Trenitalia will be let back into Nice directly.

Thank you all so much! Right now it appears there is no train from Nice to Ventimiglia on Saturday March 28th. Maybe a glitch, but it shows the schedule the day before and after. Questions:
1: Should I get a private transfer from my hotel (7am to 8am) to Ventimiglia station so I don't have to worry? We need to make the 9am train from Ventimiglia to Varenna-Esino.
2: I've heard taxi/uber may also be an option but make sure they will take me to Ventimiglia first (bc some may not want to cross border).
Or another option you suggest.