You can try these steps to reset the computer-it won't delete any personal data on it.
1. Disconnect the computer from the main power.
2. If there are any USB device connected, disconnect it. Disconnect also the mouse and Keyboard.
3. Now press and hold the power button for at least 30 seconds. Then release the power button.
4. Reconnect the power to the computer and turn it back on.
If the computer is still beeping, it will suffer a hardware failure. A constant beeping means that the memory RAM modules are not correctly seated or they are corrupted. You can try to reconnect them. The memory RAM modules are connected near the letter "E" on this image-note that the image is only as a reference, but it's very similar to your particular computer:
And here is a guide on how to reconnect the memory RAM modules:
If your computer has two RAM modules connected, try to guess if one of them is bad. Disconnect only one of the two modules, leaving the other one connected. Then power up the computer. If it stills beeping, exchange the modules and try to power up the computer again.
If none of this has worked, your computer will need to be services, because either the PSU unit or the Motherboard are bad. Any way, don't worry about the data inside the computer, you won't loose it. It's stored on the hard drive, and this error-the continuous beeping-doesn't affect the hard drive.
Regards! If that helped don't forget to accept my answer!