Can I number put numbers on cards?

Is there a way that I can get my vocabulary deck to display numbers on my cards? The reason why I want to do this is because I am starting to have quite a few words that have nearly the same definition. If there were numbers on all the cards than maybe, they would give me a hint to what word I need to guess based on the number. I want the numbers to increase from my oldest card to my newest cards. I have a basic and reverse card type on all the cards, so I need to know how to apply numbers onto both the basic and reverse card for each word. Would this even work? If not, how do I find all the words that have similar definitions?

Anki does not have such a feature. Rather than using arbitrary numbers, I’d recommend editing the text when the prompt is ambiguous.

It is possible, if you give the cards a unique ID in the order of their creation. To do this, you would have to export the deck to CSV and add an additional column in e.g. LibreOffice Calc. Export the whole deck as an Anki Deck package, and then delete the cards in the deck, then import your updated cards. Adding a column, of course, means that you must update the Note Type before importing the cards into a new deck.

However, adding a number (or colour or indeed some other memory aid) does not sound like a wise way to distinguish similar cards. You would do better, I think, by distinguishing them in the translation — i.e. distinguish the Front or Reverse of the card, so you know the difference. That will help you learn better as well as learning what distinguishes those similar words, phrases, or meanings.