Can someone recommend (or provide) a good explainer for buying Treasury Bonds?

There's a lot of posts about US treasuries potentially hitting 7% soon. I only started investing a few years ago and I've never paid any attention to bonds because a) the returns were non-existent with basically no interest rate and b) I'm young so doesn't really gel with my risk tolerance/investing horizon.

So how exactly does a rando like me buy a 7% bond, especially as someone in the UK. You're probably all aware our gilt market went to shit last year which makes me hesitant to get involved with them.

Moreover, if and when bonds do hit 7%, why on earth wouldn't or shouldn't I just invest everything I have into them and hold until they mature?

I've looked around on T212 and there's all sorts of different funds/indexes for bonds, as well as the ability to buy US Treasuries directly, however, it's not particularly clear what the interest rate is.

These are the instrument details I'm presented with

I know this is a newbie question so please don't roast me, but I thought since there's a lot of talk about it that there's likely others in a similar situation to myself that'd also find any advice helpful.

Additionally, I'm assuming that currency exchange rates are going to have a part to play in all of this, so it'd be nice to get confirmation about that. My current assumption is that the interest will be paid in USD which will be beneficial for when GBP continues its decline against the dollar over time (as it has pretty reliably for the last 100 years).