OK, having looked at the Datasheet (assuming the one you posted applies to your current project), what you need is a constant current power supply [CCPS]. The Maximum Continuous Forward Current is 3.2A (at Ambient Temperature 25℃), so the CCPS will need to supply up to 3.2A (though, 3A is probably the best nominal) at a voltage up to 36V (at least). For best efficiency it should be "switch mode".
The design of a 220V to 36V, 3A efficient switch mode constant current supply is not trivial and beyond my engineering chops. I don't, as a rule, work with such high voltages. I rely on off-the-shelf solutions for such things.
Now, regarding the issue of heat: Though this module is mounted on an aluminum metal-core printed circuit board, the datasheet recommends not powering this LED Array for more than 5 seconds "without appropriate heat dissipation equipment". So, if it isn't already mounted on a heat sink, if you plan to run it for periods longer than 5 seconds (at ambient temperature of 25℃), then you'll need to mount it on a heat sink (using some sort of heat sink compound or thermal paste) or other such heat dissipation strategy. If aluminum is used, then the datasheet suggests 0.008m²/W, so at 100W the surface area of the piece of aluminum needs to be at least 0.8m². Using a 0.89M x 0.89M sheet of aluminum as a heat sink for your light is probably impractical. And figuring out the surface area of a finned heat sink is difficult (and there are other complications such as the effect of orientation, conductivity of metal and paste, etc), so I suggest you experiment by trying a fairly large heat sink and monitor the temperature of the LED Array. The max operating temperature is 60℃, so I would do a series of incremental power-up/power-down sessions and measure the temperature after each session.
For instance, power it for 5 seconds (power-up, then after 5 seconds, power-down), then check the temperature - wait for a stable reading, then 6 seconds and check the temperature, then 7 seconds, etc, until the temperature reading is the same after each time increment (or the temperature reaches 60℃, in which case, stop and try a larger heat sink) Keep in mind that it takes time for heat to flow, so the temperature of the outside of the array will lag the junction temperature. And, the junction temperature will rise quickly and might, easily, overshoot a reading of the exterior temperature. This is the reason for the incremental powering (starting at 5 seconds, which is safe even with no heat sink (assuming the ambient temperature is 25℃ -- if more than 25℃, then lower than 60℃ -- I'm trying to cover all bases, but it's difficult without writing a book

)).
Also, depending on your technique of measuring the temperature, there can be a lag between the actual temperature and the temperature reading. A non-contact thermal-pile temperature reader has, probably, the quickest response. A thermistor, slower response, etc. And, you want to be very careful to not exceed the maximum operating temperature, as you can easily damage the LED array.
Also, consider using a fan. A fan will allow you to use a smaller heat sink. You could also water cool it, but I suspect that would be overkill. As for a source of heat sinks, consider the CPU heat sink market.
And, I recommend running it at lower than 60℃. Heat ages LEDs, so the less heat the better (at least, for longevity). It becomes a trade-off between longevity and practicality in regards to the overall dimensions of the lamp.
I Googled "led lamp constant current driver 240VAC to 3A 100W" (select the "Shopping" tab) and got numerous hits for various rather inexpensive (less than $18US) supplies that should fit the bill -- mostly on eBay.