KL-AF connection at AMS

where is your train going, and how much time do you have for that?

AMS is one of the better airports in Europe for connection transfers and an hour is usually fine but it's been a couple of years since I've connected at AMS. This may help: https://www.klm.com/travel/us_en/prepare_for_travel/at_the_airport/connections/index.htm#p1

The standard transfer time at Amsterdam Airport Schiphol to a flight
within Europe is 40 minutes and 50 minutes for an intercontinental
flight.

If you do not make your next flight because of a lack of time, you
will automatically be booked on another flight. Your baggage will be
relabelled and you will not have to retrieve it or check in for the
new flight. Your new flight details can be retrieved and you can print
out your new boarding pass at a kiosk.

That said, if you must catch a train from Paris, it would be good to have a back up plan.

yeah we hope you booked that train you need to catch in Paris well in advance. you know your first flight could screw everything up if it is delayed. but that is how it goes when you gamble

AMS is pretty well organized. Assuming you arrive in AMS from the US, you will need to go through passport control. Most of the time, it is a breeze. A few of the times, though, passport control lines were long, however, they will snag folks in line with connecting flights departing in 50 minutes or less to make sure you get to your flight. Just make sure you use the bathroom prior to landing so don't waste any time trying to get to your connecting flight. Safe travels.

I need to catch the train from Paris
That's a situation which should be avoided. One can never be sure the flight is on time, Immigration will go smoothly, or the luggage won't have issues.

I had booked AF direct flight BLR-CDG but Air france rescheduled and booked me through BLR-DEL-AMS-CDG.
Earlier the plan was to reach 08:30 AM at CDG and catch train from Gare De Lyon for Basel at 2: 25 PM.
With new connection, I should be able to reach CDG by 10:45, if everything goes as per the plan.
Whenever I call AF/KLM customer service on this connection they confidently say that this is a connecting flight and I will be able to catch this flight.

It seems like Air France has greatly inconvenienced you with the schedule change, you went from a nonstop flight from Bangalore to a 2 change connection. You will have to pass through Schengen Immigration/Passport Control at AMS. Normally this is maybe a 10 minute process. But it adds time to make the connection. Air France is confident because they figure if you miss it, they will just put you on the next plane to CDG. But the next flight is in the afternoon and you will not get to CDG until around 3:00 pm.

Since it appears that Basel is your final destination, have you thought of asking them, under the circumstances, to route you into Basel from AMS? Now there is a long delay in AMS, but you will arrive in Basel at about the same time as your original plan, without the expense of the Paris-Basel train tickets.

You can take advantage of the time at AMS by storing your carry-on luggage at the left-luggage facility and taking the short train into Amsterdam to see some of the city before returning to the airport for your Basel flight.

yes, this is really unfortunate. They have cancelled all direct flight of Air France flying from India on my day of journey. They have provided me KLM connection to make me reach on the same day.
I find that there is another flight AF 1341 for CDG from AMS at 10:35 which arrives Paris around 11:50AM. I guess if i miss my 09:30AM flight then they should be book me in AF 1341 flight.
I have gone through the historical data of layover between both the flights and I find that most of the days layover is more than 60Mins ( around 70 Mins). But again it is my luck if my flight arrives on time and I am able to get the connecting flight on that day!

Having already cleared Schengen Immigration at AMS, you will just have to wait for your baggage and exit the "green" door. This will save a bit of time arriving at CDG.

"Having already cleared Schengen Immigration at CDG, you will just have to wait for your baggage and exit the "green" door. This will save a bit of time arriving at CDG."

Sam, you mentioned immigration will happen at CDG. Is it typo? My immigration should happen at AMS.

Yes, typo, I corrected. And yes, if you are running late at AMS, let people there know and they may move you to the head of the line. I saw this myself at AMS in January.