The Farmer’s Almanacs are all done specifically for the year in which they are published, as well as being specific to a geographic location. Not helpful for the 8th century AD.
I’d imagine such a time traveling person would be viewed with suspicion so a weapon or personal protection should be one of the three. I’d go for kevlar body armor, discrete, could be worn under period clothing to blend in. As big a box of antibiotics as permissible would be another, those were plague years. For the last, I’d go for a set of DIY books with a survivalist bent, like the Foxfire series.
Then, I’d have to swallow my American distaste for such things and engratiate myself to the local lord as quickly as possible, lol.
Well, you COULD bring a taser,tell his Lordship how things are going to be, and if he demurs, make his ass do the funky chicken.