Questions about Einhell CE-BC 4M

Yes, you can, that's what the charger is for. You can also use it to charge a 12 V car battery, but it will take about four times as long as with a charger that delivers 15 A.

The device is far too weak for this, it should have much more amperes. It is only suitable for charging small 12 volt batteries. To "bypass" a car battery, i.e. to start a car engine with a discharged battery, you need a charged second starter battery that can supply the starter current of at least 60 amperes immediately or a device with the corresponding power.

The maximum A charging current is what the charger can charge per hour. A normal car battery has from 50 to 80 Ah. This means you can divide the Ah of the battery with the max charging capacity and you obtain the hours you need to fully charge the battery. Low charging capacity means more hour to charge.