I believe it depends on whether or not you have the model with discrete graphics or not. With discrete graphics you will likely be limited to the msata drives. I've installed a 2.5 drive in my E7450 but I have a unit without the discrete graphics. Simply remove the bracket that holds the msata drive and drop in a 2.5 drive.
I have Intel Graphics card. I hope that I can replace this hard drive. I saw this bracket on some movies on youtube. I saw two version of motherboards, ant this was strange for me.
I thought that it was a mistake.
Yes, it's a frame that holds the msata drive. Disconnect the entire frame, including the msata drive and you can then replace it with a standard 2.5" SSD. The frame is screwed in but there is no problem leaving the new drive without screws. Very simple to do but obviously you need to do either a fresh install or clone your existing drive with an external USB enclosure prior to replacing. Works either way.