You can carry the following Spanish consonant sounds over into Portuguese with little or no modification.
b* d* g* p t k (of como) f s m n r (of pero)
A special word needs to be said about the b, d and g sounds starred above. These symbols refer only to the often-called ‘hard’ varieties of these sounds, as heard in bien, donde and gano when these words occur first in an utterance. Portuguese does not have the ‘soft’ varieties of these sounds that occur between Spanish vowels and certain other places in that language.
Presumably you remember what is meant by ‘soft’ and ‘hard’ in this context. You probably know, for example, that the d of Spanish nada is considerably ‘softer’ than either d of donde. It is something like the th of English ‘this’. Sometimes the Spanish speaker seems to pass over it so lightly, so softly, that it all but disappears, and you hear something which we might write as na’a.
None of this ever happens in Portuguese. The d of the Portuguese word nada is a firm—a ‘hard’—d sound much as we English speakers understand and recognize a d sound.
Likewise, the b of Spanish suba is considered to be a soft sound, since the speaker’s lips do not close all the way during its production. But in the Portuguese word suba the lips are closed all the way on the b sound and the result is a sound which is very nearly the same as our familiar English b sound.
The same comparison can be drawn with regard to the g. Observe, for example, the difference between the slightly soft g of Spanish pago and the harder g of Portuguese pago.
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