What three months can and cannot buy
Fluent in ninety days is a marketing line. Not going to happen, and anyone selling it knows that.
B1 is a different question. Handling daily life, saying what you need in more than one way, following the answer that comes back: that is reachable in three months if you are ruthless about what you skip. The plan below is built for someone moving to Portugal with a date in the diary, and it leaves out most of what a language course would cover.
Weeks 1 to 4: get your ears working
The first month is almost entirely about sound, and it is the month people want to skip. Grammar can wait. If you cannot decode what a native speaker is doing to their vowels, everything you learn afterwards sits in a part of your brain that conversation never reaches.
- Week 1. Sounds only. The "sh" endings, the nasal vowels, the e that vanishes. Shadow greetings until they come out dark and swallowed rather than tidy.
- Week 2. The first 500 words, through spaced repetition, every noun learned with its article. A mesa, not mesa. Doing this now saves months of gender guesswork later.
- Week 3. Present tense of ser, estar, ter, ir, drilled to the point of reflex. These four carry an enormous share of ordinary speech.
- Week 4. Sentence frames you can drop anything into: Eu gostava de..., Onde é que fica...
Weeks 5 to 8: learn to tell a story
Conversation is mostly people telling each other what happened. Without the past tenses you can ask for things and not much else, which gets old quickly for both parties.
- Week 5. Pretérito perfeito, for things that finished. Ontem eu fui..., Eu comprei... Write three sentences about your day, every night, badly.
- Week 6. Pretérito imperfeito, for habits and description. This is the one that lets you say what you used to do and where you grew up, which is where conversations start becoming personal rather than transactional.
- Week 7. Pronoun placement after the verb: vi-o, disse-lhe. Brazilian materials will pull you the other way; ignore them for now.
- Week 8. Two graded stories a day, and no dictionary. Guess from context and be wrong sometimes. Guessing is the skill you are building.
Weeks 9 to 12: open your mouth
Everything so far has been input. The last month has to be output, and it will be uncomfortable in a way the first eight weeks were not.