Robert Johnson52

you mostly just pick them up over time honestly, but theres a handful you really do need to know early on or youll be lost. QRZ is probably the most common one youll hear on voice, it basically means "who is calling me" or sometimes just used to call CQ in a roundabout way. QSY means change frequency, QRT means youre shutting down or stopping transmission, QTH is your location. those four right there will cover a huge chunk of what you hear day to day.
the 88 thing is kind of old school ham slang for "love and kisses" and its usually used between people who know each other well or sometimes toward a female operator, though you dont hear it as much anymore. 73 is best regards basically, not really goodbye specifically even though everyone uses it that way. and yeah 55 means good luck but almost nobody uses that one. the Q codes go way back to maritime and telegraph days so theres a whole long list of them but most are pretty obscure and you wont hear half of them in regular use.

Honestly, physical QSL cards have diminished greatly in the last 20 years due to time, post office visits, and costs. I've moved almost entirely to LoTW and eQSL, only sending paper cards for truly special contacts. Many hams send a card for first contact with a station for their collections but the digital systems handle 95% of my confirmations now.

totally normal to be confused by this stuff at first, honestly even some folks whove been licensed for years get fuzzy on the details. the 10 minute rule is kind of the outer limit, not a target, so you dont need to be counting down a timer. in practice on a net youre going to ID at check-in and when you sign off and thats usually more than enough to stay legal because the exchanges are short anyway.
the NTS traffic thing is its own whole world, those formal nets have their own procedures that can feel weird if youre used to casual ragchew or a simple info net. some of those ops are just very by-the-book and thats fine, it serves a purpose when traffic actually needs to get somewhere reliably.
as for missing your check-in, waiting for the second call-round is the polite move yeah. most net controls will do a second pass specifically for folks who didnt get in the first time. jumping in mid-net can step on someone else if youre not careful, especially if the frequency is busy. just wait it out, net control usually appreciates people who dont cause chaos on the frequency

honestly i was in the same boat when i started. the one that tripped me up forever was QRN vs QRM, i kept mixing them up. i just eventually remembered it as RM = man-made (the M) and RN = natural. probably dumb but it worked for me lol
also QRO is the opposite of QRP, means running high power. you see that a lot in contest threads when people are debating whether someone was running legal limits

been thinking about doing that front end mod i keep seeing mentioned for better weak signal stuff. got the service manual but wondering if its actually worth it or just theoretical improvement. my location is pretty noisy so not sure if it would even help much
also saw something about a different crystal oscillator swap but that one looks way more involved

I was in the same boat when I upgraded. Honestly the thing that helped me most was just using the ARRL's frequency chart PDF, the one thats color coded by license class. Its not the official legal document but it translates the Part 97 stuff into something a normal person can actually read. Just keep in mind like the other guy probably said its not 100% the same as the FCC rules so if you ever really need to know for sure, go to the source.
the 60 meter thing is genuinely confusing btw, dont feel bad if that part doesnt make sense right away. its channelized and the power limit is calculated differently than everywhere else. i just kind of avoid it for now lol

i just got mine last spring and tbh im still not sure i understand half the theory lol. but i passed so theres that. the 50 ohm impedance stuff and the filter questions were the ones that got me, i kept mixing up bandpass and notch filter responses on the diagrams. just kept drilling the question pool until i could recognize the answers even if i couldnt fully explain why.
the extra HF segments are real though, i noticed it right away on 40 meters especially at night when things get crowded

honestly same question when i started lol. i just kind of do it when i feel like the other person might not catch a letter, like over a noisy path or if someones just getting started and might not recognize my call. one thing i picked up though is during nets they usually want phonetics every time you ID, the NCS will often ask for it if you dont. took me a couple sessions to figure that out the embarassing way

yeah the self spotting thing tripped me up on my first couple activations too. i downloaded the SOTA Goat app and it works great when i have signal but half the summits i do the cell coverage is basically nonexistent. i ended up just texting my wife before i left the car and she spots me from home using the app, works really well as long as im roughly on schedule which... doesnt always happen when im scrambling up a hillside with a pack on haha. anyway nice work getting it done, 6 contacts is plenty to qualify and the first one is always the most stressful one.