Yes of course you can add the second internal hard drive in your desktop computer and laptop but there are few things that you will have to check before adding the second internal hard drive in PC like power adapter, SATA port, space, etc.
Usually, all computers can accommodate two internal hard drives and if you like then you can add up to six internal hard drives in your computer that will be the best option if you wish to keep a backup of your data. One internal hard drive can be used to create a backup, so, if your data gets corrupted or the first hard drive gets crashed then you can still use the data which is safely saved in the second internal hard drive.
Moreover, you can easily add the second hard drive in your computer at home. There are hundreds of YouTube videos that you can watch to add the internal hard drive in your computer system.
What are the requirements for adding a second internal hard drive?
First of all, you need to check the number of SATA ports available in the computer system and in case a free SATA port is not available then you will have to buy a SATA card that can be used to connect the second internal hard drive.
Second, you need to check whether the existing power adapter is capable of supporting the additional hard drive or not. If it is not able to provide sufficient power to two hard drives then again you will have to install an additional power adapter or install the port to connect both internal hard drives.
Third, you need to see If there is enough space to adjust the second internal hard drive or not. Usually, desktop computers have a 3.5-inch bay which can be used for the additional hard drive.
Fourth, check whether the SATA is long enough to make the connection, else you will have to buy the new one in order to make a proper connection.
To install the additional hard drive you will need to power off the computer then unscrew the CPU and check for the SATA port, power adapter, and case slot to insert the additional internal hard drive. If you are not sure about adding the hard drive at home then take professional help from the technician who could easily add the second internal hard drive. However, if you will read the above-mentioned points then it will save you money as you exactly know whether the internal hard drive can be added or not.
Anyways if you use two internal hard drives, it will save your money as high storage capacity internal hard drives are expensive as compared to the low storage hard drives which is always a better option.