My laptop must always be on the power, otherwise it will not work. What can I do to recharge the battery?
Then your battery is probably broken. Buy new…
Usually nothing at all. When the time comes, the battery is usually flat.
The battery is probably defective. Replace the battery with a new one and it should run again.
Then sound like the battery has run out. This usually happens when the device ages or does not perform the charging process properly, such as leaving the charger too long. You can't do much.
Search for the laptop (brand, model) on the Internet and you will get support for everything. Otherwise, search for the model on Google and add the battery and order a new one.
This usually means that the battery is dead. You don't have to buy an original battery straight from an older device. Replacement kits in a suitable design are available for a fairly low price. Just don't buy the cheapest ramsch.