Do I need to sign 'I' before 'want'?
In ASL, pronouns are often dropped if the context is clear. You can simply sign 'want' and 'food' to mean 'I want food', as the subject 'I' is implied when you are expressing your own desire.
How do I sign 'food' to complete the phrase?
To sign 'food', pinch your fingers and thumb together to form a flattened 'O' handshape. Bring this handshape to your mouth and tap it against your lips a couple of times.
Can I use this sign for wanting things other than food?
Yes! The sign shown is the general sign for 'want'. You can use it to express a desire for objects, actions, or anything else by simply pairing it with the appropriate sign.