If I have a +2 oxidation number do I give up or accept electrons?​

Give up 2 electrons.

Explanation:

Is this ever a good question!!!

Electrons have a minus charge

Protons have a plus charge.

You need to understand it thoroughly.  I used to explain it this way.

Suppose the protons and electrons are playing a game and the electrons commit a foul that leaves them with 2 men short.

That means there are 2 unguarded plus's around. The result is that the minuses have lost two men who are in the sin bin. (I watch a lot of hockey).

So a +2 means that the electrons have lost two of their players to penalties.

Put in the vocabulary of your question, you give up 2 electrons.

the product of the pressure and volume is also constant