Below are Free programs that I recommend to Install.
Avast This is a Great Anti-Virus program. There is a paid upgrade but recommend the free version.
Libre Office This is very similar to Microsoft Office.
This one is for Windows only.Ccleaner Keeping your computer clean and in order is always a good idea. This is a powerful program. If you use this please make sure you know what your doing. If you are a Linux user then I recommend BleachBit