If you believe that the MS antivirus is causing your slow start-up time, you can disable it by following these steps:
- Press the Windows key + R to open the Run command box.
- Type in "gpedit.msc" and press Enter to open the Group Policy Editor.
- In the left-hand pane, navigate to Computer Configuration > Administrative Templates > Windows Components > Windows Defender Antivirus.
- In the right-hand pane, double-click on "Turn off Windows Defender Antivirus".
- Select the "Enabled" option, and then click "Apply" and "OK".
This will disable Windows Defender Antivirus on your computer.
If you want to install another free antivirus program, you can consider using Avast, AVG, or Avira. These are all reputable free antivirus programs that you can download from their official websites.
As for your question about Defender and Bitdefender, no, they are not the same thing. Windows Defender is a built-in antivirus program that comes with Windows 10, while Bitdefender is a third-party antivirus program that you can download and install separately. Both programs serve the same purpose of protecting your computer from viruses and malware, but they have different features and capabilities.