Hey everyone, I am brand new and have some questions!

I will just answer question 1 for now:

A. Kanto, Johto, Hoenn and Sinnoh are the fictional regions where the console games were set. They do not impact spawn mechanics in Pokemon Go (except during certain events).

B. Baby Pokemon do not spawn in the wild and must be hatched from eggs. A few Pokemon species (Absol, Mawile and Shinx) can only be acquired through raids. There are also Pokemon species that only spawn in certain real-life regions; see https://pokemongo.gamepress.gg/regional-pokemon-list for more details.

I'll continue from above.

2) The standard red Pokeball has no modifier. Great Balls provide a 1.5 multiplier, and Ultra Balls a 2.0.

The actual capture rate depends on the species base rate (some are much easier than other), which is then modified by various factors, including the aforementioned ball modifiers, the level of the pokemon, if a berry is used, the quality of the throw (nice, great, excellent, and if a curve ball is used), and which type medals you have earned.

3) Check out this site, which ranks all the pokemon in PvP: https://pvpoke.com/rankings/all/1500/overall/

It won't tell you where you can find them unfortunately. That's basically down to luck, but some will be fairly common in your area.

4) IVs are a often debated topic. There is no right answer but, in my opinion, IVs are a little overrated.

Generally speaking, I like for those mons I use for raids to be as good as possible, i.e. high IVs. For PvP it matters very little to me - I normally pick something that will get me as close to the league CP threshold as possible.

For lucky pokemon, it's just a decreased startdust cost. Candy costs are the same, and performance is otherwise identical aside from the fact they have high IVs by default.

Your question 2 is kind of a complicated question, because of what CP is. The answer is yes and no: it depends on the level of the Pokemon. CP is kind of an obscuring number. In the game, Pokemon have IVs and Levels as separate units, in addition to their base stats that make them a species. CP is a combination of all this factors into one number. A low-level but high-IV pokemon could have the same CP as a high-level but low-IV pokemon.

So a 250cp pidgey, might be greenish-yellow if it's a 100% perfect level 13. But it might be solidly yellow if it's a 0% level 17.5. (Oh yeah, also each power up is 'half a level').

For question 4, there's a lot of difference of opinions. For Raids, The most important factor is breakpoints (check out the breakpoint calculator). As long as you reach the damage output you want to, it doesn't really matter what IVs your pokemon has. But, if your Pokemon has bad IVs, it needs to be powered up to a higher level to reach those thresholds, costing a lot more candy and stardust.

For PVP, IVs matter less because of the CP caps in the first two tiers. It's slightly better to have high DEF and HP IVs and lower ATK IVs, because of the CP cap, but that's only super super slight a difference and is pokemon-specific.

Lucky pokemon are guaranteed really good stats (even better than the ones you get from raids and eggs-12/12/12 vs. 10/10/10 for ATK/DEF/HP). Luckies don't save you candies for powering or evolution, but they do save you on stardust. Starting out the game, it's hard to get enough candies for everything to evolve and then power them up etc. But as the game progresses, stardust becomes the limiting factor, and the most valuable resource.

For Raids, a good rule of thumb is not to power up anything you can find in the wild (eg, eeveelutions, abra/alakazam, machop/machamp, exeggutors) but use the high-level ones you catch in the wild. This saves long term on stardust, and as you level your account, you encounter higher and higher level pokemon. Once you hit level 30, you can get level 35 pokemon that are weather-boosted in the wild. Evolving the level 33 eevee into a vaporeon is going to be a lot stronger than the 90% one you hatched from an egg and is level 20, regardless of IVs. Obviously if you have the choice between two of the same level (or within 2-3 levels) go with the higher IV one.

Adding to the above answers:

tl;dr: For raids, good IVs mean you need to spend less candy/dust. For pvp, getting close to the CP cap is more important overall than getting specific IVs.

To understand the usefulness of IVs, you have to understand 'breakpoints'. Pokemon Go calculates damage based on atk vs defense, rounded down. If you look at the breakpoint calculator here on gamepress, you'll see that for each matchup and IV combination, there's a specific level at which your damage will go up by one, or the damage you take will go down by 1. This makes very little difference for charge moves (if you're doing 30 dmg 3 times, an extra 3 damage is nothing special). But for fast moves, it makes a big difference - you often get 30-40 more damage out of a pokemon in a raid by hitting a breakpoint, either by doing 1 more damage with each fast move, or by surviving another charge move from the raid boss.

Most pokemon with at least 10 in their IVs will be able to hit most breakpoints at some level. However a 10 atk pokemon might hit an atk breakpoint at lvl 35, while a 15 atk pokemon would hit it at 30. It's MUCH cheaper (in dust and candy) to get to 30 than 35. This is the most important thing about IVs for raids. However, the higher a pokemon's base stats, the less IVs make a difference (eg. for mewtwo, you can pretty much ignore IVs).

For pvp, it's much more of a mixed bag. Usually, a perfect pokemon is actually *not* optimal in pvp (unless it's master league, which not many people play). The most important thing is getting as close to the CP cap as possible (1500 for great league, 2500 for ultra). Beyond that, different IV spreads will give you advantages in some cases and disadvantages in others. This depends on the IVs of your opponent, which is not predictable at all. So my advice would be to choose pvp pokemon based on how close they can get to the CP cap, and don't worry too much about the IVs.