Is it a good start to DCA into VOO?

VOO also has a slightly cheaper expense ratio than SPY, which is one of the other big names in US ETFs.

The other approach is: consider investing in a global ETF instead of a purely US one. This will hedge your investment against a prolonged US depression. VWRD (also by Vanguard) and IWDA (by Blackrock) both track the MSCI World Index I think.

That would be a good idea! Index investing is a good way to get started in investing with relatively low effort and minimal knowledge required. It is diversified, low cost and historically has done very well in the past, netting 9.8% per annum since the early 1900s! This will allow you to build up the foundation for your portfolio before you choose to venture into individual stocks or more niche ETFs.