Use the lsblk command to view your available disk devices and their mount points. The output of lsblk removes the /dev/ prefix from full device paths. Here xvda  is root device and -xvda1  is partitions.  /  indicate the mount point.  On the other hand xvdf no partition and mount point. 

[ec2-user ~]$ lsblk
NAME    MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
xvda    202:0    0    8G  0 disk
-xvda1  202:1    0    8G  0 part /
xvdf    202:80   0   10G  0 disk

Lets say we want to add disk xvdf , So first we need to determine our file system. New volumes are raw block devices, and we must create a file system to use them. We can determine file system by following command - 

[ec2-user ~]$ sudo file -s /dev/xvdf
/dev/xvdf: data

If the output shows simply data, then there is no file system on the device

[ec2-user ~]$ sudo file -s /dev/xvda1
/dev/xvda1: SGI XFS filesystem data (blksz 4096, inosz 512, v2 dirs)

output shows a root device with the XFS file system.

Also we can use lsblk -f to get file information. We can get  information about all of the attached devices to the instance.

[ec2-user ~]$ sudo lsblk -f

Display all available LVM block 

sudo lvmdiskscan
Output
  /dev/sda   [     200.00 GiB] 
  /dev/sdb   [     100.00 GiB] 
  2 disks
  2 partitions
  0 LVM physical volume whole disks
  0 LVM physical volumes

It'll return all information. Now if you want to know specific disk which is using lvm you can use - 

lvmdiskscan -l
Output
  WARNING: only considering LVM devices
  /dev/vda3                 [     <99.00 GiB] LVM physical volume
  0 LVM physical volume whole disks
  1 LVM physical volume

The pvscan command searches all available devices for LVM physical volumes - 

sudo pvscan
Output
  PV /dev/sda   VG LVMVolGroup     lvm2 [200.00 GiB / 0    free]
  PV /dev/sdb   VG LVMVolGroup     lvm2 [100.00 GiB / 10.00 GiB free]
  Total: 2 [299.99 GiB] / in use: 2 [299.99 GiB] / in no VG: 0 [0   ]

pvs and pvdisplay can find more additional information - 

if we also want to discover logical extents that have been mapped to each volume we can use -m option to the pvdisplay command.

sudo pvdisplay -m

To discover available volume group we can use - 

vgscan
Output
  Reading all physical volumes.  This may take a while...
  Found volume group "LVMVolGroup" using metadata type lvm2

here LVMVolGroup is the volume group where we can add more space and manage logical volume group.