Cannot enter BIOS on Inspiron 3671

try replace cmos battery with a new one.  then try RTC reset to clear cmos

• Press and hold the power button for thirty (30-35) seconds.
• The computer RTC Reset occurs after you release the power button.

Are you using a GPU card or onboard graphics?

@bradthetechnut​ Sorry for the late reply. My Inspiron 3671 has the Intel(R) UHD Graphics 630.

Thanks for the info.  Sometimes, that happens with a GPU card - can't see BIOS.  But I see you're using onboard graphics.

Does your system boot into Windows normally outside of not being able to see BIOS?

@bradthetechnut​ Yes. The computer has no problem restarting. I've tried using F2 and F12 but the computer won't go into bios, it just puts the monitor into sleep mode and the screen turns black. I have to press the monitor power button on and press any keys on the keyboard to reboot. I haven't tried the other methods I saw on YouTube for this situation. To use the Recovery Method or a Command Prompt task. I'm  hesitate to try them since I'm not computer savvy and I get nervous whether the computer is going to start up or not. I want to thank you for replying to my post. I appreciate your expertise very much. Any suggestions you can provide I'll appreciate. Thanks again and have a great day.

As per redxps' suggestion:  How to Perform a BIOS or CMOS Reset and Clear the NVRAM on Dell Computers  On yours, it's as simple as pressing and holding the power button for 30 sec.

Did you also try replacing the size 2032 CMOS battery as redxps suggested?

Outside of that, the only other thing I can think of is try a different monitor and/or different monitor connection.  If it's hooked up HDMI, try DP.