Dell Inspiron 7559 Cannot Get Into Bios After Switching to Legacy Boot

This is an odd situation but after a certain Windows 10 update, the Dell logo never showed up anymore on boot up. Everything else was fine, although I couldn't access BIOS after this update unless I used Windows 10. Skip to just recently, I had to switch my boot order to an external hard drive. I had to change to legacy boot for this. Little did I know this locked me out of BIOS. I tried a lot of key combinations, nothing worked. From what I gathered, I have to leave out my battery to get very low or I need to take out the CMOS battery. The BIOS was up to date with no mods. Any help on other things I can do to fix this would be appreciated, I just want to get back the UEFI.