I know there's a lot of conflicting advice here haha but as someone who learned Spanish and was pretty fluent at it back when I still used it, I found it detrimental to look up the words I didn't know. Instead, I tried to just guess what they meant based on the context and kept reading, even if I maybe only understood 80% of the story. If a word kept reappearing and I couldn't guess what it meant by the context, then I'd look it up, but only when it keeps reappearing. But I think it's important to try to understand words from the context bc in actual conversations, you won't have time to pause what the other person is saying to look up a word haha.

I'd also recommend reading in a genre you actually like. If you find Hemingway boring, that's fine! Just find what you like to read in Portuguese and find similar genres in English. I've seen a couple people recommend YA or children's series which is fine if that's what you like, but made up words make reading harder imo, so I don't really like to read foreign fantasy, but one genre that's usually pretty straightforward is detective/crime novels. Just plain old English with a usually straight forward plot, and might keep you hooked enough to keep on reading.

And then yeah, might be the obvious advice but just keep reading lol. You'll understand more and more with time. Nothing beats experience for learning.