partitioning – Unable to configure RAID 0 on my ubuntu machine

I am new to the RAID concept, sorry if this is a redundant question.

lsblk output:

sda      8:0    0 931.5G  0 disk 
├─sda1   8:1    0 220.6G  0 part 
├─sda2   8:2    0  19.1G  0 part /
└─sda3   8:3    0   393G  0 part 
sdb      8:16   1  14.7G  0 disk 
├─sdb1   8:17   1     1K  0 part 
└─sdb5   8:21   1  14.6G  0 part /media/saransh/SARANSH
sr0     11:0    1  1024M  0 rom  

I have been following various articles to configure RAID 0, I know I need 2 disk to perform the task, but not able to achieve this. I am trying on my local machine with OS ubuntu 20.04 LTS.

If I cant acive this with the above this with the above partition, and I don’t have another hard disk, should I follow the virtual machine method, Please suggest.

Thanks for your response in advance.
Will I be able to do it with the above partition ?