How to use queen duvet with twin bed?

Very new to the terminology and don’t really use a lot of bed etiquettes

My friend gave me a queen insert with a cover in it. I only have a twin bed and will probably not upgrade for a long time.

Obviously it’s too big for the bed so I haven’t been able to use it.

I don’t really think much of my bed except I just want my bed to be very fluffy for me to sleep on. I’ve got a mattress topper and made a nest on my bed (another fitted sheet on top filled with pillows). I also have a twin comforter.

I don’t want to waste the queen sitting in my closet.

Any suggestions?