whenever I tried to pick my laptop it completely shut down.

Hi,

If it works OK when the charger is connected but not when working on the battery only, there may be a problem with the battery.

Have you checked that the battery is fully charging OK (100%) when the charger is connected to the laptop?

If it is even so it may be failing to hold its’ charge.

Try replacing the battery and check if that resolves the problem.

Here’s a link to the ifixit Sostituzione batteria Acer Nitro 5 AN515-53-55G9 guide which should be of some help.

Here’s a link to just one supplier. It is only shown to give an idea of the cost of the part. There are other suppliers online that may suit you better. Just search for Acer Nitro 5 AN515-53-55G9 battery to get results.