HAH, you'd be surprised... in fact, all you need is electronics 3 and propulsion jamming 1, that way you can fit warp scramblers and disruptors, from there it's only a short way to your first killmail and the slippery slope to the dark side

IF you put some effort into really understanding the mechanics (not that you have to, just saying) there is a big chance you can find people that play eve for YEARS and still know less than a new person. Some people for instance have stupid leaders, that understand mechanics wrong and teach wrong stuff to the newcomers that dont want to think for themselves. Eve really is complex enough to make that possible

Anyway, apart from my useless rabble: the best way to determine NPC strength is to look at their bounty. Apart from the tutorial rats that pay out up to 1500 isk iirc, the weakest kind of npc is worth about 4k isk, while the strongest (standard belt and mission) rats will pay around 1.5mil in bounty. There are exceptions, like rogue drones and navy rats, which dont have a bounty per se. You just would have to learn for them, but you dont need to bother as much in the start. For completeness sakes, rats (as we call npcs in eve) can have a bounty up to and over 10 mil iirc, but those are special spawns, and even they are sometimes not much harder than the strongest beltrats. (which you only find in 0.0 space)
Another way of judging npc strength would be just by the difficulty of the mission you accept (when you dont go for beltrats)
lvl1 are obviously easiest (best done in a frigate), lvl2 are a bit harder (and are aimed at cruisers), lvl3 are again a tad harder, the jump from 2 to 3 is is bigger than the jump from 1 to 2, they usually require battlecruisers. Lvl4s are the hardest missions in highsec, you tend to do them in battleships. The jump from 3 to 4 is even bigger than the jump from 1 to 3, tho!
For starters; get OUT OF YOUR ROOKIESHIP ASAP. those things are REALLY REALLY throwaway. Insure your first frigate if you must, but they are really considerably cheap. EVERYTHING is better than a rookie frigate.
edit: HAH minmatar! great choice, you picked the hard mode

no really, most challenging to learn, most rewarding to fly, no questions asked.
The really bright side of this is: you got the rifter, which is commonly accepted as the best t1 frigate in the whole game. If you like to go fast and shoot projectile guns that sound cool, you will love minmatar. also, mad max design.
Anyway, things to consider:
if you want to mine, youre looking at the burst (maybe the probe, if you dont care so much about efficiency but cargo hold, iirc) and the scythe as your step up. should you decide to become a dedicated miner (can be boring) you should look at a really dedicated path, too. means: barges, beeline. get industrial skills. and the like. If you dont do that, you are better off with pve for money making.
for combat you want to get a rifter. if youre looking at cruisers, you have a lot of options. rupture is good for pvp and pve, stabber is mostly a pvp ship and needs some experience before it can be flown properly. its like a biiiig frigate, its a weird ship, a little "special". so is the bellicose. very misunderstood ship. you can, however, fit it a bit... counterintuitive to get you through your first hours of lvl2 missions. (by fitting lots and lots of large shield extenders and small weapons). Flying a bellicose in pvp is a whole different matter entirely and would require its own thread

so basically... a good path for combat is rifter (stop there and focus on training and practice if pvp) and then rupture / hurricane. Be disciplined, train armor tanks and guns, so you have those ships effective soon. you can do quite some interesting stuff with minnie ships and shield skills, but for a young character thats wasted time. what you want is focus focus focus on small areas you can make use of, so you are useful and entertained sooner.
If you look at minmatar battleships, stuff gets a bit complicated. they are quite hard to fly properly, but dont listen to people that complain. the typhoon alone is worth being minmatar. if you aim at lvl4 pve (which is a common moneymaking pastime in eve), you want to train armor tanking, cruise missiles and medium artillery (yeah, im serious) and some dronage.
Should get you started.