1- It should I am not sure of the laser power requirements. You have 12v30A max 360W, the machine only needs about 12v 3A 36W so as long as it requires less than 320W you should be fine.
2-keeping both on there will sacrafice speed and precision on both tools, more so on the laser and you probably don’t want your optics near all that dust.
3-lots of video tutorials on fusion. Not going to work with a laser. Steep learning curve, really steep. You should learn the basics on estlcam first. Fusion has at least 5x’s the options. you really need to know what every single one of them means or you will get bad cuts.