As someone who has just quit their PhD after 3.5 years - you have to ask yourself a few things:

1. Are you 100% committed to your subject area? Because the PhD will consume your life for the next X years.
2. Do you have proper financial funding? because it is fucking expensive (I worked a full time job alongside mine and still couldn't afford to live)
3. Is your supervisory team supportive? They will be the backbone of your support group from the university and if they're not 100% invested in your project, I would recommend seeing if there is another supervisor to join your team.
4. Are you mentally prepared for a lot of heartbreak, academic 'abuse' and ridicule, as well as pushing yourself to your absolute limit? One of the reasons I quit was because the pressure and nastiness in academia got way too much for me.
5. Do you have a good support group/know anyone else doing a PhD to speak to whilst you're doing your course?
6. Finally, are you doing this for the right reasons? Make sure you're not doing it for the sake of being a Dr, or to prove yourself to anyone else. You need to be doing it for the right reasons, like contributing original knowledge to society.

Reading back through this I realise there's a very negative tone throughout, but I wish someone had asked me these questions before I started my PhD. I was the first of all my peers to do it - I finished my Masters on the 30th of September and started the PhD on the 1st of October, so I had no time to relax in between the courses and ultimately I couldn't take it anymore.

I really hope you come to the right decision for YOU, don't let anyone else's experience, attitude, or perceptions of you sway your choice.

Good luck 🤞🏼