question

[Bleach=Chlorine?]

Regarding the skimmer and adding CYA to it:
The skimmer is the opening at the water-line that has the basket that collects bugs, leaves, etc. You can either dump the CYA into the skimmer and it will get caught up in the filter medium until it dissolves or you can add it to a sock and just leave the sock sitting in the skimmer. Using a sock means you can backwash and not have to worry about losing undisolved CYA.
Pool Volume/CYA Dosage:
According to your pool specs, 16 ft Diam by 3.3 ft deep the volume of your pool is 4975.872 gallons. A level of 30ppm CYA would require 1lb & 3 ozs of CYA. I would add just under that amount to a sock, leave it in your skimmer and check the CYA level at the end of the week.
Safe Swimming:
Since the CYA is slowly dissolving the level will not be dangerous (especially if it is dissolving in a sock) so you will be fine to swim in the water. Also, a Cl level of 3ppm is fine, I would try to keep it around that level.
TA/pH Level:
Will let someone else tackle that one!