Take the grate away, unless you’re burning coal. When lighting, you want both vents fully opened, and leave them both fully opened until it’s roaring away, and kindling below is glowing. Only then do you close the primary vent, dependant and lots of things, the draw of your chimney, type of wood etc, this may take as long as 10 minutes.
Leave the secondary vent fully open for a wee while, just to make sure the fire is going, then start to use that as a control. A wee tip, when lighting, leave the door slightly ajar, just a 5mm gap, this’ll help get it going.
Don’t worry, I remember when I first got mine, I read somewhere that it may take as long as 6 ,moths to get to know your stove, and I can totally concur!. Enjoy fella.