I have partitioned a WD My Passport 500Gb external drive into two parts, a 200Gb Time Machine Back Up and a 300Gb Manual storage of certain files.
Is there any way to delete the Time Machine back up and have just 1 full 500Gb with the files in the 300Gb partition still intact?
And if this works, is it possible to have Time Machine back up into the new 500Gb drive while having a folder for a manual storage?
— Mark I
You can, in some cases, change the partitions on a drive without destroying the data. It is risky, though. You use Disk Utility to remove to unwanted partition, and then expand the other partition to the full size. There are a lot of steps and it may be difficult to do if you aren't familiar with Disk Utility.
Another way is to copy the data you want to save to a second drive, then reformat the first drive and copy the data back.
Time Machine really wants to be able to use the whole drive (or partition) so it can manage space on the drive and know when you are about to run out and it needs to recycle old files. So you can't just backup to a folder.
Hard drive are cheap, but your data may be priceless (photos, etc). I always recommend backing up to a separate drive that is dedicated to backups.
Think about this: if you share a backup drive with other stuff, how is that "other stuff" getting backup up? It isn't. That "Manual storage of certain files" isn't getting backup up at all now, which can get you into trouble if the drive goes bad.