I need to optimise images easy and fast

I need to compress and resize a lot of images for my website. I have read this sub and other bits online and some mention subscribing to cloudlfare pro plan and letting their lossy image do the work. Others mention using LiteSpeed cache and then some say to use an image optimisation plugin.

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What is my best method of completing this task as quick as possible and in a simple way. I'm still learning the ropes of website building and I am on a shared hosting plan.