I had configured the donation system assuming the payment method PAYPAL; however, when the donor try to donate in the unique/single donation option the donor directs to INTERNATIONAL PAYPAL, which requires donation in USD dollar instead of BRL Reais, as were are based on Brazil. As well as, the whole page is in english.
On the other hand, in the same system but in the recurring donation option the system works correctly directing the donor to PAYPAL Brazil (donation in Reais) in a portuguese page.