People say practice makes perfect. It does not. Perfect practice makes perfect.
The reasoning is simple. If you do something wrong and then repeat that wrong thing over and over, you become perfect at making that mistake. Nothing else improves. You need the right method before repetition does you any good.
This applies directly to English
Plenty of people move abroad, manage conversation, handle their job in English, and stay in that job for four, five, seven years. But everything they say sits inside the boundaries of that job.
I know people working in offices, in logistics, in marketing, in all sorts. At work they communicate perfectly well. Put them in a social setting, among friends, in a conversation with any depth to it, and they cannot do it.
So "I work here, so my English works" does not necessarily mean the English is good enough.
What good enough actually means
English is good enough when it is sufficient to make friends and have a real conversation. The kind two Vietnamese people have sitting together, about love, work, health, the things underneath the surface.
English for genuinely belonging somewhere, for living well and being happy in an English-speaking society, has to reach that level. And reaching it requires either the right environment or a deliberate way of practising.
One route is volunteering. Charities working with older people are particularly good, because they generally have time and are glad to talk properly with you. That is how you end up able to discuss something other than work.