First off, how do you actually purchase them?
When I look at the page below and click on the 20 or 30 year with 4.6% interest, it takes me to a page with lots of info, none of which is about purchasing. And when I look at the faq it talks about bidding at an auction with no straightforward info how to do that. When I click on Today's Auction, stuff about competitive and noncompetitive results. How do I actually purchase the damn thing?
https://treasurydirect.gov/marketable-securities/treasury-bonds/
Second, is the 4.6% 20 or 30 year compound interest?
When I search for this, I find that Series I bonds are compounded twice a year but when I click on them, the rate is 3.11% not 4.6%. So is the 4.6% not compounded?
https://www.treasurydirect.gov/savings-bonds/i-bonds/