Question about loans and credit cards (UK/Scot)

I saw a deal on Amazon that I can sign up for a Barclays card and get a product for cheaper as you can get a 50 bucks gift card for signing up for the credit card.

I rarely actually use Amazon, but I thought, this might not be a bad idea as I could just use that card for Amazon purchases if and when I need them. It would help me build more credit

I am eligible and could cover the costs.

But, the card is with Barclays, a different bank. And it's got HIGH APR like 28.6%. And I would be only using it in these rare occasions to buy from Amazon and pay off quickly. I currently do this with my own credit card with my existing bank.

I currently use my own credit card for day to day spending and pay off each month. Again just to build credit.

My question is this: I want to take out a personal loan later this year. And I have been initially approved for this earlier, but I haven't taken the loan out yet (good thing too as I wanna check the fine print with interest now the world is at war… secondary question, are interest rates on personal loans impacted by the war as well like they say mortgages will be?? …I assume so but I can hope they won't right??)…

Will taking out a credit card like this hurt my credit score and will I able able to take out a loan later this year?