How to Format A Portable Hard Drive for Mac and PC

Sorry Apple community, but my main computer is a PC. Unfortunately, it's being repaired and I won't have it for 6 weeks. So, for that time, my Mac has become my main computer. However, I'm running into issues with my WD Passport. I can't write to it. It looks like that might be the result of my hard drive being formatted for PC. (I had the hard drive and have been using it long before getting a Mac, was even a thought).

I have Paragon NTFS installed on my Seagate hard drive to be able to use on PC and Mac, but I'm reading that people installing it on a WD hard drive are having issues and files getting corrupted when they plug the hard drive back into their PC. Has anyone heard of this? I can't afford that risk. Does anyone have any suggestions where I can write to my PC formatted portable hard drive?

My other question is, I've been looking at getting a new/larger capacity hard drive, even before my PC went in for repair. How should it be formatted so that I can use it interchangably between PC and Mac?