Should I remove my credit card to not be charged again?

No, you do not.

If you want to never be charged again, just cancel your subscription. You will not charged with a cancelled subscription.

You can of course also remove your credit card details too if you want, but there is no need to do so and it will have no effect.

Note: If you do not want to be charged, please do not just remove your credit card without cancelling your subscription. The system would then continue to try to charge a non working credit card which leads to all kinds of technical issues. If you do not want to be charged anymore, cancel your subscriptions. You will 100% never be charged again – guaranteed!