You may want to print out the sticky I wrote at the top entitled, "So you want a cap and ball revolver?"
Lots of good info in that sticky. Copy and paste it to a Word document, then print it out. Don't neglect to read the comments that follow it. Lots of good info in them too.
Between the original post, and comments, you should be well armed (every pun intended) with enough information to shoot those revolvers.
Because they're brass-framed, they are not as strong. You'll want to keep loads to no more than 22 grains of FFFG black powder, or equivalent.
A brass-framed .44 Navy is what I started with back about 1970, when I was 15. It was not well made (a lot of junk cap and ball reproductions in the 1960s and 1970s) but was a good teacher. Later, I bought better quality revolvers, with steel frames.
You'll have a lot of fun with those revolvers, but remember to clean them right away. Black powder and its substitutes are corrosive and will rust the steel parts of your revolver. Given enough time, it will even cause corrosion on the frame frame.
Buy a box of .454 inch balls, some No. 11 caps, a can of FFFG black powder or Pyrodex (Hodgdon 777 is not recommended for brass-framed revolvers, according to Hodgdon), some felt Wonder Wads and some Bore Butter and you'll be set. Smear the Bore Butter on the cylinder pin to help shrug off binding from fouling and you'll be set.
Don't forget to wear eye and ear protection.
Let us know how you're doing with those pistols.
Welcome to a very fascinating hobby!
"And lo, did I see an ugly cat. Smoke. Brimstone. Holes in parchment. And this ugly cat was much amused." --- The Prophesies of Gatodamus (1503 - 1566)