Well luckily for most new hires you can expect reserve, which is the easiest bid to make. Just choose days off you request (keeping in mind there will be grouping rules and mandatory coverage days "unstacking" that the software will take into account).

There is a learning curve to the PBS bidding software but there are many videos, guides and pilots that can help when that becomes important. Until then it's best to focus all effort on your new aircraft and procedures. Some pilots that learn PBS, use it masterfully, and some pilots 20yrs later keep asking how did I get that?