Should be a very small bolt on the bottom of each fork leg facing backwards to drain the fluid. You can add your carefully measured amounts of fork fluid through the hole in the spring retainer up top (once you take the allen bolt out of it).
I use Bel Ray fork oil because my local shop carries it. $15 a quart, but that's good for two years. Most important thing is to stick with one brand. Fork oil weights aren't held to national/international standards like other oils, so Bel Ray's 10weight might be different from somebody elses.
If you're feeling frugal you can use red ATF.