So lets say I have this;
playerParam = { ['Username'] = plr.Name, ['Id'] = plr.PlayerId }
( Ignore the fact I haven't defined plr)
How would I be able to select one of these items in a table?
There are two ways.
playerParam.Username
or playerParam["Username"]
This is called indexing.
For more info on indexing and tables in general, please see this question.