IMO it depends on how much you want to spend, risk tolerance and your expectations for the underlying stock/ETF. My core trade is ATM about 30 days out, but I might go 1-2 strikes ITM if the option is cheap enough. I don't do it often, but if the ATM price is too expensive for position sizing I might go to the nearest strike ATM plus or minus the underlying ATR(14) * 1.5 depending on whether it's a call or put.

Roughly speaking, the Delta of the option you are looking at is the perceived percentage that ticker will be ITM at expiration.

For example, if you are looking at an OTM put with a .30 delta, it means that strike has roughly a 30% chance of being ITM on expiration.

Most ATM strikes will be close to .50 delta, or 50% chance of being ITM at expiration.
ITM strikes will be > ,50 delta, climbing higher the further ITM you go.
OTM strikes will be < .50 delta, dropping lower the further OTM you go.

Like all odds, using delta as a percentage chance of ITM applies only when looking at large data sets. If you select 1,000 random tickers and purchase one OTM put at .30 delta for each one, then approximately 700 of those will expire worthless and approximately 300 will be ITM.

I think if you check you will find that your definition of delta is incorrect...
https://www.investopedia.com/articles/optioninvestor/03/021403.asp#:~:text=Key%20Takeaways,gamma%2C%20theta%2C%20and%20vega.

Sometimes delta is used as a proxy for the probability that an option will expire in the money. According to this technique, an out of the money call with a delta of 0.36 has a probability of expiring in the money of 36%. An in the money put with a delta of 0.64 has a 64% chance of expiring in the money (for puts you take the absolute value of delta).

We have said above that the sum of absolute values of delta of a call and a put with the same strike is one. This is in line with the probability idea. When you have a call and a put on the same underlying and with the same strike price, you can be sure that one of them will expire in the money and the other will expire out of the money (unless, of course, the underlying stock ends up exactly equal to the strike price and both options expire exactly at the money). Therefore, the sum of the probabilities should be 100% (and the sum of the absolute values of deltas should be one).
Delta is only an indication, not a guarantee of probabilities

Using delta as a probability proxy is only an estimate and in practice it is not precise. It assumes random market movement and rational (unbiased) valuation of options – conditions rarely met in practice. An option’s delta results from the market (that means people) valuing options as related to the underlying asset. We all know that market expectations are often wrong.

*** Disclaimer *** StockFetcher.com does not endorse or suggest any of the securities which are returned in any of the searches or filters. They are provided purely for informational and research purposes. StockFetcher.com does not recommend particular securities. StockFetcher.com, Vestyl Software, L.L.C. and involved content providers shall not be liable for any errors or delays in the content, or for any actions taken based on the content.