This site is very DIY. Read the forums. The
Build Reports will show you what a properly built board looks like.
Troubleshooting will show you what kind of stuff can go wrong and how we go about fixing it.
This post tells you everything you'll need to know for a successful build.
Parts selection is at the discretion of the builder, meaning that when the BOM says you need a 100nF capacitor, you have to figure out what type is best and what will fit. Unless you are an experienced builder, the first few pedals will require a fair amount of homework on your part.
Here's a little help to get you started on parts:
Resistors - get 1/8W 1% metal film from Tayda, Mouser or DigiKey. Some 1/4W will fit easily, some won't. Read the specs before you buy. Pad spacings are 0.3" (7.5mm), resistors are usually placed on 0.1" centers.
Capacitors - the rectangular ones between 470pF and 1uF are film. 10% tolerance, 50V - 100V rating is good. Get them from Small Bear,
Mammoth, Tayda, DigiKey or Mouser. The capacitors have generally the same pad spacing as resistors. Smaller value caps are ceramic or silver mica. Larger value round caps are electrolytic: aluminum or tantalum. Always use quality parts. Buying semiconductors on Amazon and eBay is a crap-shoot. Lotta counterfeit parts on those sites.