Configure on LXQt ‐ Fcitx

1. Hit Super key and search for "fcitx 5 configuration" and open it.

2. On the window that popped up, search input method named "openbangla keyboard". Click on the item saying "OpenBangla Keyboard" and add it by clicking on ⬅️ (left arrow) and click apply.

3. Now you can write switch you layout by using hotkeys, which is by default Ctrl + Space.