I'd highly recommend learning the program since it is "industry standard". What that ultimately means at the end of the day is it's a well known program, and it only helps to know how to use the program. A lot of jobs, both art related and not art related can benefit from the usage of this program. Photoshop is a powerful program and it can honestly mesh well with a lot of fields including photography, illustration, graphic design, game development, 3D Modeling, fashion design, animation, website design, etc.
If you're looking to "get your feet wet" before committing to a monthly subscription, I'd recommend practicing with programs like Krita/ GIMP to get an idea of how similar programs work and what to expect. I will say, both programs offer alot of similar features, but some more advance features aren't necessarily available like they are in photoshop.