I have 3 drives (& 1 logical) in total. My C: drive/D: the logical drive/F: drive/ & G: drive. I want to merge the F: & G: drive. Both drives already have been formatted & data backed up. Is it possible? & How can I do that? Your help is appreciated.

Better if you explained more of what you mean by Merging... because I, for one, do not quite understand what you wish to do...

I want to turn 2 physical hard drives into 1 logical drive. Can I do that? & if yes then How can I do that?

It doesn't seem likely, but I would be delighted to learn I am wrong.

Yes, you can do this no problem. Read up on a MS invention called Dynamic Disk. Mind you, this can cause you a lot of problems one day when you may want to reinstall your OS or use those drives in another system.

Of course, if the drives happen to be of similar size, you can set up software RAID0 too.