Lenovo: How to enter or boot to Safe Mode in Windows 7, 8, 8.1 and 10

Safe mode is a troubleshooting option for Windows that starts your computer in a limited state. Only the basic files and drivers necessary to run Windows are started. Safe mode is useful for troubleshooting problems with programs and drivers that might not start correctly or that might prevent Windows from starting correctly. 

https://support.lenovo.com/es/es/solutions/ht116905