This is the 2739th most frequent Russian word.
желательно
Preferably; desirably.
The word 'желательно' is used here to express that eating properly is recommended or preferred.
Для здорового образа жизни желательно питаться правильно.
For a healthy lifestyle, it is advisable to eat properly.
In this context, 'желательно' indicates that asking questions immediately is the preferred course of action.
Если у вас есть вопросы, желательно спросить сразу.
If you have questions, it is advisable to ask them immediately.
Here, 'желательно' is used to express a wish or expectation for punctuality among participants.