Don't focus on "performing" but on having a ton of fun. Your odds of doing "well" by any objective performance metric your first time out is about 1 in 5000.
For the car, in order:
Pass tech (it is easy but a lot of people fail regardless)
Reliability
Braking
Reliability
Handling
Reliability
Driver comfort
Reliability
Then maybe handling
Reliability
When all other avenues are perfect, more power while not sacrificing...
Reliability
For the team, also in order:
Make sure all you understand and agree on why you are at the track and the type of car/team you are building
Member retention and meeting continued financial requirements
Being predictable on track
Member retention
Situational awarness as traffic management done well is faster than a 30% bump in horespower and also the hardest skill to master after...
Member retention (seriously, the average team loses 75-150% of its members by the green flag on race #2)
Clean, fast pit stops
Ability to follow a race strategy
Member retention
Assigning, understanding and executing non-driving roles well (crew chief, cook, mechanic, team mom, logistics officer, etc)
Driver training
Member retention
A few notes on some of the above. Getting 4-5 idiots to agree to and follow through on all the time and financial requirements to get your first race is highly unlikely. Vehicle prep (everyone has a different number) for most new teams is about $4500 then everyone has to have their personal safety gear ($700-2000 to own, like $125 weekend to rent) and $350'ish in entry fees and and about $4-700 in consumables, test and tune, food, ice, beer. You also have to get the car to and from the track, sleep somewhere, bring spares, tools, fuel jugs, refill jugs, water, food, etc...all of these things go better if someone is really good at logistics.
Traffic management is overwhelming for most for at least the first 5 laps and you don't learn it at test and tune or virtually all other forms of racing. 100+ cars on two miles of track with 11+ turns is (and this is not how it happens) one car every 100' or so or about 9 cars per turn. More common is you will end up in a group of 12 cars trying to pass you at roughly the same pace with 3-4 cars that are slower than you in the mix all at the same moment. Running clean with no gblack flags is about 1 second a lap faster PER BLACK FLAG for the first two for the whole weekend. Get a third black flag and you can usually count on that being the equivalent of 5 seconds a lap (totally rough calculations but the third will have you off track for 30 minutes minimum in most cases).
The only thing that takes you off track longer than black flags (unless you have crash damage) is stuff breaking you did not anticipate breaking...heck, and mechanic issue that gets you towed in will cause a 15-30 delay even if its just plain running out of fuel. Blown engine...usually many more hours. Non-unitized wheel bearing failure and swap can be done by the best teams in about 20 minutes but it will likely take your team 40-60 minutes if you have the parts and it goes well.