It's difficult to suggest the best option without knowing more about your financial situation, but in general here are a few thoughts:
1. You mentioned dividends, but there is also the option of interest. The taxing of those two given your financial situation is key. Dividends could be taxed at 0, 15, or 20%. Interest would be at whatever ordinary income tax bracket you reside in, which could be as low as 10%, 12%, or 22%+. The reason I highlighted interest is because there can be less financial risk with investments that provide interest, like CD's or US Treasury notes/bonds. Anything with dividends (like stocks) is going to have more market risk. This should be the first decision you should make. Once you do that, then you can consider the following...
2. If you select bonds/CDs, you have to address interest rate risk. If you buy a ladder of bonds or CD's, then you can reduce some of the risk of interest rates rising. Given your advanced age, maybe a 5 year bond/CD ladder with $100k in each year (year 1 through year 5) would be decent. That would require you to figure out how to buy the 5 bonds/CD's. And the end of each year, the maturing $100k would be reinvested in another 5 year bond, or you could decide to stop continuing the ladder. and just leave each $100k in some sort of short-term investment. You could also build shorter ladders, like 1-3 years.
3. If you are interested in CD's, make sure you DON'T buy callable CD's. Also make sure you don't have too much money at one bank where you exceed federal FDIC insurance. If you have a brokerage account, you could buy CD's from various different highly safe banks. Overall this is pretty safe and you'd earn ~3.4-3.6%. It would be taxed like interest/ordinary income.
4. Rather than CD's, you could also build a 5 year ladder of US Treasury notes/bonds. That would be very safe and you'd earn ~3.5-3.7% on the ladder. The only other complication is that your yearly taxes will have a little bit more complexity from holding the treasury bonds. It's not a big deal, but you have to figure it out the first time. It would be taxed like interest/ordinary income.
5. If building a bond/CD ladder is too complex, you could buy just 1 bond ETF. But if you do that, you want to make sure to not create too much interest rate risk. For example, if you bought an ETF and interest rates skyrocketed, some ETF values would drop significantly. One way to reduce that risk is to buy a bond ETF that has bonds with maturity dates not too far in the future. For example, the Vanguard Government Short-Term ETF (VGSH) holds US treasuries with maturities around 2 years. This would earn about 3.5% and be really easy to buy and just hold. And it's safe because it's invested only in government bonds. This is a decent option.
6. If you want dividends, which come from stocks, then the SCHD ETF recommendation is a good example. Vanguard has a similar ETF, VYM. These distribute about 2.4% right now, and the underlying stocks in them will move up and down with the market. You need to be careful with this option because stock market valuations are at very high levels historically. If your time horizon is 7-10 years+, it might be fine. I get the impression your time horizon is shorter.
7. Finally, there is the whole class of high dividend stocks like described above: mlp's, EPD, etc. There are also ETF's that specialize in these higher dividend securities so that you woudn't have to be a stock picker and hold multiple stocks. However, these are somewhat controversial. Some people love them and others don't. I held them for many years, and for several reasons, they weren't a good fit for me long-term.