Proof

Source: Kajetan Sumila on Unsplash

Proof is evidence that something is true.

• The police don't have any proof that he is guilty of the crime.
• You need proof of identity, your passport or driving licence, before they will let you in.

The verb is prove and means to show something is true.

• I can't prove anything but I think she is lying.
• If you really love me, then prove it.
• I'm sure that I am right. Can you prove that I am wrong?

Proof is an uncountable noun.

• You need a proof to show that he is guilty. 😡 
• You need proof/some proof.  😍 
• Where are the proofs?  😡 
• Where is the proof?  😍 

Vamos a hacer la prueba : Let's try.
Tienes que hacer una prueba de nivel : You have to do a level test.
El médico me hizo más pruebas : The doctor did some more tests on me.
El nuevo secretario está a prueba : The new secretary is on a trial period/on trial.
El actor tuvo que hacer muchas pruebas : The actor had to do many auditions.
Prueba un poco de este pescado : Try/taste a bit of this fish
Déjame que pruebe yo : Let me try/have a go
Deberías probar el abrigo antes de comprarlo : You should try on the coat before buying it.

So you can see that you can translate probar/una prueba in different ways, depending on the context. In none of the above sentences is it translated as prove/proof.

What's the strangest food you have ever tried?

Do you like trying on clothes?

Have you ever been in a situation where you suspected something but didn't have proof?