Assuming you would be approved for any credit card, you generally want the card that gives you the most benefits.

Exactly which card would do that depends on what you use it for.

Generally, cash back is a good measure, as rewards in other ways can be highly variable and sometimes worse than cash back.

So the best card for a person making thousands of dollars in purchases a month and traveling is quite different from someone paying for groceries, gas, and entertainment.

You should use the regional subreddits for your area, as I do not know what the UK has to offer.

From your other response:

Will be using it for general expenditure, like clothes and food etc. Doubt it would be more than 800 per month

What is general expenditure? To maximize cash back, you should focus on the categories you spend in.

I would look for more than 2% cash back as a general rule for the majority of your purchases.

Groceries and gas are often the large categories for non travelers on credit cards.

Retail specific rewards can be useful too if you use a particular place often enough (for example, in the USA, we have the Amazon Visa card, which gives 5% cashback on Amazon plus rewards for purchases everywhere else. The UK option is not nearly as good for some reason...with a rewards rate of less than 1% on the Amazon MasterCard).