How to perform a tune up on a 2001-2005 Honda Civic EX?

Please only respond if you have REAL experience! Or CERTIFIED mechanic. Thank you.
I just bought a 2001 Honda Civic EX in pretty good condition, passed smogged with flying colors & a mechanic. No problems. Everything works and only 115K miles. Clean title. My plan is to change the oil, oil filter, PCV valve, air/cabin filter & spark plugs. It all seems relatively simple, just screwing and unscrewing. And torquing down the spark plugs carefully.

I have three questions:
A) any common things to be cautious of when doing these things?

B) since i'm going to do it myself, i don't mind spending the extra $10 for the best parts. I plan to use valvoline or bosch motor oil 5-30/bosch oil filter. NGK spark plugs. K&N filter. Good brand PCV valve(welcome to recommend). And do this every 5000k miles. Good? Or bad?

C) also with this car what else should i be doing to keep her healthy and live a long life?

LET ME KNOW WHAT I'm DOING WRONG/ WHAT TO DO RIGHT thanks again for helping. And thank you for reading.

The car passed the smog inspection with "flying colors". It doesn't NEED a tune-up! Spark plugs in a modern engine are good for 100,000 miles. An oil and filter change is OK, and you can change air filters if they are Really dirty, but for the rest of it…

SAVE YOUR MONEY! You'll need it to pay for insurance.

You just bought this car and there's one thing that should have been done at 110,000 miles. The cam belt MUST be replaced at this mileage. This is an interference engine and as such if the belt breaks you will have serious engine damage. Unless you know positively that the belt was replaced at 110,000 miles you need to have this done today. Also replace the water pump which is driven by the cam belt. This has probably not been done and that is why they traded it. It will cost around $900 at a dealer and around half that at an independent shop. Failure to replace the belt can cost you big money in repairs if it breaks. This is not a DIY job unless you know what you are doing. Changing the oil/filter every 5,000 miles is about right. Change the air & cabin filter every 30,000 miles. The spark plugs should be be replaced every 100,000 miles but it is likely they were not. Pull one out and look see. If it is new then do not replace them. If you do replace them apply anti-sieze compound to the spark plug threads and torque to 13 ft/lbs. I would not recommend you use a K&N air filter. They are coated with oil which can damage the MAF sensor if you coat them with too much oil. They really provide no benefit other than you can just clean them instead of replacing them. They will provide no real horsepower gain or better fuel mileage in normal driving. Good for high rpm situations like racing but not a daily driver. Any major brand of oil is fine but you should use what Honda recommends which is SAE 5w-20 weigh oil and not 5w-30. With 115,000 miles on the odometer I would recommend you purchase a High Mileage oil. Bosch, Purolator, & Wix, are excellent filters but avoid Fram. One critical thing with a Civic is to never over tighten the lug nuts or you will warp the rotors. Torque them to 80 lb/ft and no more. Also be careful when tightening the oil drain plug and always replace the.10 cent crush washer or you will distort the pan a cause a leak or ruin the pan altogether. Tighten it to 25 lb/ft of torque. The Civic is an excellent car that will give you great service if you take care of it.