I did 2 years in halls, first year part-catered and second year self-catered, so I can definitely give you the pros and cons of each.
Part-catered was helpful for me since I was very anxious before going to uni and I also did not know how to cook apart from mac and cheese and ramen. The pros are that you have food prepared for you and you don't have to worry about grocery shopping or what you're going to eat that night. The cons however, is that catered is more expensive and honestly you'd save a lot more if you cooked for yourself. You also have to eat at set mealtimes, so if you get back late or wake up late, you'd probably miss a dinner or breakfast, which hurts when you know how much you paid to be catered. It also means that if you want to have a meal with your friends, you miss out on your catered meals (unless you eat twice or time it so that you get back in time). I also had days where I wouldn't be hungry or felt ill, but then there was the hassle of getting my food since it was already paid for.
I honestly preferred self-catered. I never cooked for myself before so it was very intimidating to me in first year, but once you learn one or two dishes, learning more becomes quite easy and there's a lot of simple, filling and healthy meals you can cook. The main reason I preferred self-catered was that I can eat at my own times, instead of having to wake up early or rush back to get my food. At my uni, the dining halls was in another building and while it was less than a minute's walk, it meant I would have to get dressed to get food, rather than just walk two steps to the kitchen in my pajamas.
Also think about your preferences; uni meals are usually pretty balanced with vegetarian and fish options and salad/veggies available with each meal. But if you're a fussy eater, you may prefer being able to control your food. I personally am a picky eater and for the most part, there were only one or two days where I didn't like any options available, but small things like me not liking runny eggs made quite a few breakfasts annoying since they cook things for the majority.
But look into your uni options! A friend in Canada who was catered had a 24/7 buffet style of catering. So if you have very flexible mealtimes and money isn't an issue, it can be helpful if you're catered. In my experience being self-catered wasn't nearly as difficult as I thought it would be, it helped me learn a lot more dishes and improved my confidence in the kitchen, saved a lot of money and I could eat when and what I wanted. Keep in mind that most catered accommodations may have a fridge or microwave for the hall to share but often don't provide kitchens. I was a bit lucky as my accommodation offered part-catered so there was a full kitchen still available, but if you sometimes want to cook something you're craving or feel hungry even though you've already eaten, preparing meals might be a challenge.
So see what your uni provides and what options there are, but I'd honestly recommend self-catered. Catered is convenient, but the convenience doesn't really play that big a role compared to the pros of being self-catered, especially if you have set meal times which takes away from the convenience of it all, in my opinion.
If you have any more questions, feel free to post them and I'll be happy to answer!
Catered might be helpful if you don't want to decide what you should cook or eat everyday. It's also helpful during exams period especially when you might not have a lot of time to cook and ready meals are therefore super handy. But the downside is that catered halls only have a small kitchen with a microwave and fridge so you cannot even make noodles for yourself at night (unless you can settle with microwaved noodles). Don't worry about missing meals though- colleges have a list you can put down your name on and can get the food packed if you're busy elsewhere!
I personally love cooking and want to be able to decide what and when I eat, which is why I went for self-catered. Plus you have about 6 people in your flat so you can save a lot of money and energy if each of you cooks for everybody once a week. Being able to cook your own food is a life skill as well and uni is the best place to practice that. Yeah sometimes it can get a bit boring or you might be too tired to cook, but you can always prepare a big batch and store it for later or get a takeaway or a tesco meal deal.