dual boot – How do I used the unusable disk space?

I would like to dual boot Windows 10 with Ubuntu. I resized the sda2 partition (which says “Windows Recovery Environment”) to 86.5 GB. There is now an “unusable” thing. There is also sda4, should I just resize sda4 to use the unusable disk space?

Edit: I resized sda2 to its original size, what do I do now?