Yes.
OK, seriously...I am basically doing this (separating the posts this way) to (a) be funny (I got to have a little fun with this) and (b) to establish an important baseline. Although many graduate programs are now beginning to not require the GREs, they are still optional at just about every graduate program in the country, and still required at about 90% of them. Maybe this will change (I'm writing this in 2023), but for right now, that's the deal.
Also, there's the question of which GREs to take. What I'm mostly talking about here is the General GRE. There is also a Subject GRE in Psychology. It used to be that both are required. Now, only clinical Ph.D. and PsyD. programs require the subject GRE, and even then, most do not. So, you should check with the programs that you are interested in if this is a requirement. The subject GRE is like the final exam to a very weird Introduction to Psychology class (one that would take about 2 years to teach). But, basically, it covers the content of the Gleitman et al., Introductory Book. It's a truly weird test. Really look at the fine print of your applications, and only take it if you have to.
But back to the Generals. Yes, you should take the General GREs. The Math and English parts are similar in structure to the SAT. The math part tends to be a little easier while the English part tends to be a little harder.
The reason to take them is pretty simple. Right now, you're in college. You're used to taking tests. You have taken a lot of them. And if you're apply now, you might need these scores. But let's pretend that you want to take some time., and don't plan on applying for 2-3 yeras. Well, when you leave college, you won't have taken a test for a while. You'll be out of practice, and that's going to hurt you. You won't remember how to study for things, because that's not a skill you often use outside of school. You're never more prepared for this test than in your senior year of college, even if you don't feel prepared. And the scores last for 5 years, so they will still be applicable 2-3 years down the road.
And like the SAT, you can retake them, and you can report your best performance on each test individually (so if you did better on math the first time, but better on English the second, you can just report the better scores).
So, yes, for seniors, this might be an extra bit...But I do highly recommend doing it once (in the Fall usually), just in case.