There are a number of tools that will remove some of the bloatware that is preinstalled on most Windows PC's, such as PC Decrapifier and alternatives.
Uninstalling OneDrive is a bit more complex, and may pose complications if you registered Windows using the on-line password option. You can remove OneDrive using the Command line.. First kill any active OneDrive process, then (for a 64-bit system), enter:
%SystemRoot%\SysWOW64\OneDriveSetup.exe /uninstall
Defender, however, should not be removed directly -- instead, install almost any anti-malware suite, such as Avast!, Kaspersky etc. This will disable Defender, get rid of MS warnings that your system is unprotected, and ensure that your are not leaving the system wide open to malware. See PC Mag for one set of AV reviews.