No mate. That's the bitter truth. This may be the 100th thread of this kind, and these threads come, and after few days die a natural death because, in the first place, there's the need but no plan. Secondly, this becomes just a chat, and that too not aimed at English.
Let me tell you, I have never seen - NEVER seen, a person who writes in Sinhala and include English words in English letters, speak English. That's very primitive, and that drives you towards broken English and broken Sinhala. It never improves the language.
If you write in Sinhala, write in Sinhala even the English word. Write "car" in Sinhalese. (now I have to write Sinhala in English letters because I am on the phone. But you can type in Sinhala here.)
And read and listen to English as much as possible. There's no way that you learn English while watching Sinhala tele dramas and listening to Bus songs.
Commit yourself to English, that's the only way.
Sadly, what you have denounced is the truth.