The practicalities are that yes, you are likely to need a relevant degree. I just went for a biology job and they clearly asked for a degree in biology or another science. I’m pretty sure that now and again it is overlooked, but people with a relevant degree are generally going to get better access to specific teaching jobs.
With a humanities degree, you are probably more suited to a humanities subject or English.
I have personally been teaching since 2002. I enjoy my job, but it is very difficult and I do sometimes look forward to retirement a little too much. The hours are much longer than people realise and you will work unpaid in your own time more than you think you will, especially to begin with.
Expectations of teachers tend to be extremely high, sometimes unreasonable and you will absolutely not stay in your job more than a handful of years, unless you’ve become a teacher for the right reasons…that you have a passion for education and working with children.
I am also a middle leader and student teacher mentor and my students often have really bad days. Days when their planning fails; the pupils behave atrociously; they put their foot in it with SLT; forget to attend an important meeting or forget to be professional for a moment and end up receiving a complaint from a parent, or even one of the pupils. I’ve had students in tears, saying how they can’t do this.
BUT, if you really want to be a teacher (and it definitely not for the holidays because believe me, that isn’t worth it) then go for it. Know it will be harder than you can imagine and you will need to be resilient, but if you come out the other side, you will have days where you feel the rewards. Those days when a child comes to say goodbye at the end of year 11, with a beautiful hand written note of thanks for everything you’ve done for them, or that day when a year 7 pupils let’s you know that you’re their favourite teacher because…that’s why I do it.
SLT are a headache. The LEA is a headache. The paperwork is an utter nightmare. The hours are long. But there are moments of joy that I just couldn’t imagine experiencing in any other profession.
Best of luck and if you need any advice, please do post.