Portuguese native here. Overall, portuguese is difficult and very challenging, because we have a tons of verbs and the past, present and future of verbs, has different and unique ways to say/write correctly. Is very common for a foreigns express with some errors , and mostly says the verbs on infinitive. But we understand them without any problem.

And yeah, spanish and portuguese is kinda similar, its natural some people joins both. Our national football coach is spanish and we see how he try to speak portuguese, but sometimes he join both languages.