For charging it recommends 2.4 amps or higher the iPad charger is only 2.1 amps, will this be ok? Should i use a 61W Mac book pro charger- or will that brake it and cause fire? how should it be charged safely?
No you can’t fry the 20100, it will just take what it needs. If you connect a 2.1A charger to the 20100 which can take upto 2.4A, the 20100 will charge a little slower (10% slower roughly) but the issue is that 2.1A output charger is running at its maximum for hours so you’d risk wearing out the charger faster. If you connect the 61W output charger it will be obviously much less loaded, but it may default to 2A so end up even slower charger.
The ideal is a 2.4A output charger of which practically everything from Anker will do, so a Powerport2, 4, 5, 6…
What you own now will work almost as good as anything you could buy.
Perfect, thank you @nigelhealy