I think the wood in the Amazon photo is Acacia wood, but I’d be a bit leary with them not naming the wood and just referring to it as “Solid Natural Wood”. I saw someone in the reviews mentioned getting different woods as well. So if you think you got Acacia wood, I’d skip to #4 below. If you’re not sure, I would go to #3. 
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Test a scrap piece if ya got it. (Not an option for you.)
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If you know what wood it is but don’t know a good setting, you can look at something called a “Janka Scale” which lists the hardness rating of wood. You can find the hardness for the material you want to use, then find the hardness for a known wood with a similar hardness that you know the setting for and that will give you a good starting point.
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When I’m in doubt, I start around 1000 speed, 270 LPI and 50-60ish power for a not too deep engraving using “vary power”. (If you aren’t sure what the different settings do, see “working with manual mode” link below.) I make sure and secure the material so it will not move and if I want it darker/deeper after the first run, I just run the engraving again. I always suggest starting very conservative with a lower setting because you can always run the engraving again and take away more material, but you can’t put it back.
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Search the forum for the answer
@shop knows his stuff and I would start here if you have Acacia wood. vvvvvv