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 $ sudo blkid

 /dev/mapper/vg_proj-lvswap: UUID="e2ce33bc-d4c9-4f82-80f3-665410e039b8" 
 TYPE="swap"
 /dev/mapper/vg_proj-lvora: UUID="53a8dcc2-170f-47c7-99ff-6bc9d0abc3fc" 
 TYPE="ext4"
 /dev/mapper/vg_proj-lvdata: UUID="62bdbde7-598a-4a21-9e6c-7222a0bdd224" 
 TYPE="ext4"

There are already some default entries in fstab and i created three logical volumes (one is swap) as mentioned above and need to enter them in fstab. In which format i need to enter these details in fstab to mount properly ? How to ensure that there are no errors so that it will not cause problem after reboot ?

Note: Swap partitions/LVs won't be mounted as such; instead, they will be enabled with swapon.

With LVM, there is no real advantage to using the UUID over using the LV device name, as the LVM subsystem already searches all disks for LVM UUIDs when starting up and whenever new devices are detected. So I prefer using names.

With LVM, there's one extra trick. You can usually specify the name of a LVM LV in two forms: either the actual name /dev/mapper/<VG name>-<LV name> or the legacy LVMv1 compatibility alias: /dev/<VG name>/<LV name>. Usually both forms are equivalent, but when specifying the root filesystem, you might want to stick with the current syntax as the initramfs might not implement the legacy compatibility.

So, you could specify them like this:

/dev/mapper/vg_proj-lvswap none swap defaults 0 0
/dev/mapper/vg_proj-lvora <desired mountpoint> ext4 defaults 0 2
/dev/mapper/vg_proj-lvdata <desired mountpoint> ext4 defaults 0 2

Or like this:

/dev/vg_proj/lvswap none swap defaults 0 0
/dev/vg_proj/lvora <desired mountpoint> ext4 defaults 0 2
/dev/vg_proj/lvdata <desired mountpoint> ext4 defaults 0 2

Or using UUIDs like this:

UUID="e2ce33bc-d4c9-4f82-80f3-665410e039b8" none swap defaults 0 0
UUID="53a8dcc2-170f-47c7-99ff-6bc9d0abc3fc" <desired mountpoint> ext4 defaults 0 2
UUID="62bdbde7-598a-4a21-9e6c-7222a0bdd224" <desired mountpoint> ext4 defaults 0 2

All the above three forms should be equivalent for the computer, but in my opinion, the first two are more sysadmin-friendly than the third one.

After adding the appropriate lines to /etc/fstab and ensuring the mount point directories exist, instead of mounting the filesystems manually, you might use mount -a to tell the system to mount them based on the edited fstab file. If this results in errors, you'll know you made a typo in editing the fstab file.

(Unless, of course, your fstab file contains filesystems that are configured to be mounted, but cannot be mounted right now for whatever reason. But if that's true, those would also cause you problems at reboot, so it's still a good check.)

To enter the details within your fstab file it is firstly important to know where you can locate the fstab file. Usually, in a standard Linux build; the fstab file is located on the following filepath:

/etc/fstab

Due to the nature of this file you need to have admin/sudo privileges so ensure to execute sudo alongside your chosen text editor. The format in this case will be the following:

Format your file in order of the objects mentioned.

Device - This field fully specifies the mount device which you need to apply. I notice in your answer you have both UUID and device label, you can use one or the other.

Mount point - You then need to specify the mount point the partition or disk will be mounted. In your case it is an LVM which is a disk and that disk must reside somewhere in the file system. For example: swap. That is one component which you need for one of your disks so for example your formatting would like

INCOMPLETE EXAMPLE
/dev/mapper/vg_proj-lvswap swap

File system type - There are many types of file systems available such as ext4, ext3, xfs, zfs, swap. You need to specify the type of file system required after specifying the mount point.

Options - Once you've specified the core areas such as the file system type, label and mount point; you then need to specify how you want the kernel to treat your mounted device. There are a number of options available which can determine the behavior and purpose of your mounted FS (File System), a good reference point would be this site.
https://pclosmag.com/html/Issues/200709/page07.html

Backup option (Optional) - The next field you will need is a specification of backing up the partition you have added in a dump format. You can either add 1 if you choose to do so or simply add 0 or just ignore. This field is not important and is not required.

File system check - When a Linux system boots, the file systems need to be checked for errors on boot time depending on the level of priority added in the FSTAB file. You have three different options which you can add for your priority check ranging from 0 to 2.

0 - Ignore file system check
1 - Specify root partition
2 - File system will be checked using a program named fsck (File System Consistency Check)
More information on file system checking is here:
https://askubuntu.com/questions/9939/what-do-the-last-two-fields-in-fstab-mean
Information on fsck: https://linux.die.net/man/8/fsck

Complete example:

/dev/mapper/vg_proj-lvswap swap swap defaults 0 0

Assuming you have made your LVMs and your swap partition this is all you will need to do with a reboot. Please be careful whilst editing this file as a false entry could cause you some issues.

Once you have added all the device names to the mount points you want. Run the mount command to add these to your file system and you're good to go.

References:
https://geek-university.com/linux/etc-fstab-file/
https://wiki.archlinux.org/index.php/fstab
https://pclosmag.com/html/Issues/200709/page07.html