I bought a game recently and payed for it with Paypal. The transaction procesed without asking me my password (obviously I had purchased things before). I believe this is not very secure and I would like to be asked password every time. Where can I change my Paypal settings or unlink it altogether?

I don't think that has anything to do with itch.io; you were probably logged into PayPal already. You can only connect your account in order to receive payouts, if you're selling games here, and you'd know if that was the case. Look in your account settings, you'll notice the Payment Processors tab is under the Publisher heading.

That sounds more like "paypal one touch" to me, you must disable it from paypal, it has nothing to do with itch.

You might be right, thank you.