Ask is a verb meaning ‘put a question or seek an answer from someone’:

Can I ask you a question?

He asked me what age I was.

‘How are you?’ she asked.

We can use ask with the to-infinitive to talk about requesting something:

She asked to see Professor Fenton. (ask + to-infinitive)

We asked the City Council to help us organise a sports day. (ask + object + to-infinitive).

If you ask for something, it means that you want someone to give you something:

I always ask for extra tomato sauce on my pizza.

They asked their boss for more money, but he refused.

Don’t confuse ask for and demand. Demand means ‘ask for something forcefully’, in a way that shows we are not expecting a refusal:

We are writing to ask for your help in finding suitable accommodation in New Haven.

Not: We are writing to demand …

We use for when we request someone to give us something:

I called them to ask for more details.

Not: I called them to ask more details.