How much it takes to learn how to properly read, write, listen, and speak in English? It took me about 20 years in total, but I still cannot talk properly.
English? A word like "night" turns into "nig-hut" which kinda makes sense, but is also completely wrong. There are so many times when I have to say "No, actually you say XXX".
Speaking is fine, mostly. Though there were a few *years* where I had to say "Mommy is a woman, so you say 'she' not 'he'." as Finnish doesn't have gendered pronouns. "Your friend is a girl so you say 'her ball', not 'his ball'". That took a long time to sink in, even though he was fine when people spoke to him he'd almost always get it wrong when women/girls were involved - and even Finnish adults make those kind of mistakes quite often. ("I have a girlfriend, his name is Sally".)
When you learn a second language you have the baggage of the first language hindering you (talking about orthography here), and you normally don't start by speaking the language exclusively for 6 years before learning how to read. If you don't know what the language is supposed to sound like, of course it's hard to understand how to read in it.