what language is best to learn in the usa?

You’re very close to learn Portuguese if you know how to speak Spanish. Both languages have 75% similar vocabulary. I’m Brazilian and I can understand Spanish speakers if they speak a little slow. Some words and expressions have differences but it’s just a question of adaptation. I think you will learn quickly. French can help a little too.

If you learn Portuguese and knowing how to speak French and Spanish will be easier to you learn Italian. These four languages are most popular between Latin people.

You will be able to talk in much of the world using the native languages of the places. In America just the places where Dutch is official (Suriname and Netherlands Antilles) are exceptions. You will have the world at your feet.

English: Languages are capitalized in English, and you still lack grammatical skills.

Norwegian is my best suggestion.

You should learn English.

First try to learn fluent and grammatically correct the languages that you have enumerated.

So you know a little of the languages you listed.Try to become really good with one of them.Spanish isn't easy but it is very useful.

It would depend on where you live, but from my experience German is the most useful of those four. Hindi or Russian would also be useful.
Looking at a statistics list, Tagalog is the fourth most spoken language in the US after English, Spanish, and Mandarin, however I would assume that Tagalog is localized to just a few cities and so it may not be useful where you are.

I would recommend that you explore your city a little bit. See if there is a major community around you that speaks a language you don't know. If that doesn't work, then I would recommend you just learn a language that is important to you personally (i.e. friends, family, clients, co-workers, etc speak it).

Spanish

italian maybe? and asl is very cool to learn as well. i learned and you'd be surprised at how often you can actually use it

Portuguese is probably the easiest to learn if you already know Spanish

japanese, german, russian, and italian are amongst the largest.

African

The official language in USA is English, so learn English. After that, the only other language used in USA is Spanish, because the Spanish speaking population is so big. So, learn Spanish.

Otherwise, there is no other language necessary in USA.

I would recommend Spanish.