Best soil mix & a few questions <3

Hi RIU <3,
What is the best soil combination for a beginner? Doesnt have to be EPIC but im still trying to learn. Im germinating and planting in one month into a 5L bucket. As of now im THINKING 50% pro-mix, 25% perlite, 25% worm castings.
Questions:
1) with the soil combo above, will the Ph be off? do i need to add lime or something?
2) what fertalizer do you use and how often/how do you apply it? when do you start to apply?
3) can i use rain water to water my girl? or is creek water okay?
4) is one bag of pro-mix, perlite, and worm castings enough for 3 5L buckets?
5) what insect repellent or pest control do you use? and how often?

all help is appreciated! basically i need to know about a solid and simple soil mix and what to do about fertalizer. Thanks and please help!

1.Lime should always be added because it maintains a neutral soil ph and supplies calcium and magnesium.
2.Fertilizer can be added into the soil at the beggening of the grow and then all you need to do is water. It can also be dissolved in water and fed that way. I like to do both. I use close to the same soil mix you described except I add foxfarm marine cuisine, which is a dry mix of a lot of organic fish meal, kelp meal and a bunch of other delicious organic shit that your plants love. Its not completely organic but is "organic based". Manure, compost and other organic matter can also be added to the soil. Blue mountain organics makes a great water soluble fertilizer lineup including foliar spray if you want. Fox farm liquid ferts are always a stand by. Advanced nutrients is good but pricey. Gen hydro, earth juice, general organics are all good, stay away from miracle grow and any general chemical chelated fertilizers youd find on the cheap at walmart lowes etc.
3. Rain water is the best shit always keep that in mind and if you have use it. Creek water should be tested for 2 things, one is the ph so you know what adjustments you may have to make if your seeing deficiencies. Two is get a test trial plant going with a bag seed or pick just one plant to feed it to, chances are its fine but you don't want to go feeding random creek water that could have run off to your whole crop, if it does damage you want it to be minimal.
4. I dont know how much perlite and worm castings you have, but if your getting the 1 cuft bag i believe that its 28 liters so you should be fine.
5. You should really try and stick to organic pest control especially when flowering, pyrethrin based insecticide or neem oil is best, apply every 7-10 days plus after whenever it rains. I used liquid fence last year and had no absolutely no animal problems, in an area where i ran into multiple deer every trek out i think thats pretty impressive. I've also heard hanging bars of irish spring, and using moth balls scattered around the grow keeps animals away. Any artificial smells also work good such as hair clippings from a barber shop.

so basically im going to fill two 5L buckets. and my mix will be 25% promix, 25% Foxfarm marine cuisine, 25% permlite, and what else? 25% worm castings? does that sound right? and how was your Ph balance with your mix? exactly what was your mix? thanks!

Not quite, marine cuisine is a potent fertilizer, 25 percent would be way too much and way too expensive. Here i'll give you the mix i plan on using for this upcoming outdoor season. 20 percent worm castings, 20 percent perlite, 60 percent pro mix. Around that ratio should be fine. To that mix I add 2 tablespoons of lime per gallon of soil, and 1 tablespoon of marine cuisine per gallon. If your just using marine cuisine, and no other fertilizer spread some more of the marine cuisine around the base of the plant and light scratch it into the soil around the beggening of flowering. Also start feeding with molasses at 1-2 tablespoons per gallon of water when flowering starts.

Other things i plan on using this season if your interested.
Zeba, a cornstarched based product added to the soil mix, it absorbs 400 times its weight and water and can help extend the time in between waterings, similiar to water polymers but organic.
Myco soluble, a powder that is mixed into the water you feed the plants, contains beneficial bacteria such as mycorrhizae and trichoderma.
I also have some left over kelp meal that i'll probably be mixing into the soil.
On top of my soil mix Im feeding with the Blue mountain organics lineup, so theres no need for me to re apply marine cuisine.

Sorry about using american measurments im assuming your in canada or europe because your using liters.