Please who knows a website where I can get video tutorials on Splunk processing Language (SPL)
This is the one I use and send to my customers:
There is also the older but still valid answer's for "Hungry Newbie: Best way to learn Splunk well efficiently (shortest amount of time)?"
There are some Splunk Education videos that are good for the basics, like Basic searching in Splunk.
I also recommend these slides from a user conference presentation in 2017: https://conf.splunk.com/files/2017/slides/power-of-spl.pdf