Pls help by answering.Thank you.Need to understand before proceeding further
There is a fundamental problem with the word 'charger', which is designed to charge a battery. It is different from a 'power supply', which is designed to power a device. The two things can and generally do behave differently. They are designed to behave differently. However, people often use the two terms interchangeably, so confusing them.
Sometimes a charger is built into a device, and requires an external power supply.
Sometimes the power supply and charger are built into the same unit.
A charger should only be used with the battery it has been designed to charge.
If the power supply and device are 'dumb', then the supply should have the correct voltage rating for the device. The device may specify a small range, like 5 V +/- 0.5 V, or a big range, like 8 V to 32 V, or it may only give a single voltage figure, in which case you are probably OK with +/- 10%. The supply should provide at least the required current, the device will only use the current it requires.
Sometimes a device may be built to accept a range of voltages and possibly draw a range of currents, sometimes by communicating with a 'smart' power supply. If the power supply, device, or both are 'smart', then you have to read the manuals to see what they have been programmed to do in various circumstances.