Hi there,
So, there are several options available to you. Jobs within the psychological profession are big cans of worms. Generally speaking, yes, you'll need a psychology degree (it will be a must for any job that has "psychologist" in its title), but for other professions, like counsellors or social workers, there are many routes, some of them bypassing psychology (and some of the routes also potentially bypassing university altogether, as far as I understand, but don't quote me on that!). A lot of therapist roles will require you to do training with nebulous entry requirements. Some of this training will be proper postgraduate study, some of it could be in the form of something akin to an apprenticeship and a degree in psychology might not be absolutely necessary... but this is as far as I remember from researching this ever so briefly a while ago, so I recommend you do your own research, and a good first port of call would be the NHS career website, specifically the
psychological professions page.
Note though, that even though a psychology degree is a very handy thing to have, you can still study law (which is a very fun degree, I study psychology but you'll often catch me sneaking into law lectures because they're so good haha) and do a psychology conversion course/masters afterwards, which will be to all effects and purposes a psychology degree.
Hope this helps

SY