Hi Laura Beth - welcome to the fish forum!!
Do you have an aquarium stand that could hide a canister type filter, or do you need a filter that hangs on or in the tank itself? I have a 98 litre tank, and I run an external canister Fluval 205, which provides plenty of filtration for my needs. And it's very quiet and has good capacity for bio media.
Do you need an air pump for any specific reason? Unless you need it to run some bubble decoration, you might find that it's not needed at all, and that will greatly help the "quiet" factor.
How many fish is a wide open question. It depends on your water stats, what you like, how big the selected fish will get, etc. I have 17 fish in my tank, which is similar in size to yours, and it is at capacity, I think. (actually - I think it will be overstocked when my fish reach adult size - and then I might have to re-home some of them) If you get the typical 1-2 inch tropical community fish, then following a 1" of fish per gallon rule might be a good place to start your planning.
As you start your fishless cycle - nose around the forum at some other people's fishless cycle threads (there is one in my signature). You might want to start your own thread and update it as you go. You will get plenty of help from the senior members on this forum.
Things I wish I had known before starting my cycle:
1. If you have the funds, get an API Freshwater Master Test Kit (about $30USD) - it has a LOT of test liquid for ammonia, nitrite, nitrate, low pH, and high pH. Several hundred tests for each. Some users might eventually want to know your KH/GH (hardness), and that is available as a separate test kit.
2. Pure ammonia can be difficult to track down (ACE Hardware in the USA; Homebase in UK?)
3. Bump your tank temp to 29C/84F.
4. Bump your tank pH level up to 8.0-8.4. You can use pure sodium bicarbonate ("bicarbonate of soda" in the UK; Arm & Hammer baking soda in the USA) to raise your pH. Start out adding a small amount (like 1/2 tsp), wait 10-15 minutes, and then measure the pH to see how much it went up. Keep adding until you get it high enough.
5. "Set it and forget it": once you have your tank running with filter, heater, temp, pH level, and ammonia at 4 ppm - be PATIENT and let the process work. Some people find their tank cycles in 2 weeks, others can take months. But it does work.
That's all I could think of right off hand...post back with questions.
