Yes, you can. If you see Klarna Pay in 3 when you go to an online checkout then it is available to you. Every time you use Pay in 3, Klarna will check to see whether you can use Pay in 3 again for each additional purchase.
Borrowing more than you can afford or paying late may negatively impact your financial status and ability to obtain credit. Subject to status. Ts&Cs and late fees apply.