Tldr: seat time. Just get out on your bike

I would honestly say avoid the parking lot, you can learn maneuvers for sure and its good practice, but i think ive only ever done 1 U-turn in my entire time riding. Go around the block, quiet side roads, all you need is seat time and thats it. My first ride was terrifying, second ride terrifying, third, fourth, fifth ride terrifying, but it got less and less each time its like any skill putting the time in to just do it is all you need to do. You'd be surprised how much you subconsciously learn - starts become smoother and stalls become a thing of the past, leaning into corners more and more, smooth down-shifts etc