Are there any communities that help newbies like myself learn the fundamentals of SFV?

Every SF community I've seen is super helpful to new players. It's a difficult genre to get into. Everyone feels you on that, so they're all quick to help as well (as most got helped into the game themselves at some point).

Blocking is pretty simple; for jump attacks you have to guard standing (hold back), for crouching kicks you have to guard low (hold down and back). All standing attacks and crouching punches can be blocked either way. There are some exceptions, like ryu's forward standing medium punch (an overhead attack, it bypasses low guard).

Combos come with time. Every char has a target combo (the one shown on the command list), but also various attacks that link into each other, and attacks that can be cancelled into a special. It's important to end combos with specials, as those do permanent damage (whereas blocked 'normals' deal damage which recovers over time). A very standard combo is ryu's c.mk (crouching medium kick) into hadoken. His s.mp (standing medium punch) also combos into the c.mk, and s.mp can be combod into from a j.mk (jumping medium kick).

So if you get an opportunity to jump in (only do so if the opponent doesn't punish jumps though), you could get this off:

j.mk >^^* s.mp > c.mk xx^^** hadoken/tatsu.

*that means 'combo into'.

**that means 'cancelled into', ie some attacks can be interrupted by a special.

As for the V system, each char has a unique V skill, performed by pressing mp+mk. Ryu has a parry, which nullifies any attack as long as it's timed right, and mika can shout down a mic to make her next grab stronger. Some have different options, for example birdie can drop a banana peel, roll a can, or eat a donut. Respectively, they're executed by holding forward, neutral, or backward, while activating the v skill.

Most chars gain a bit of charge on the v bar from using their v skill (and from just taking damage). The v bar has 2 uses: while blocking, hold forward and press lp+mp+hp to perform a v reversal. Doing so consumes 1 block of the v bar, but usually knocks your opponent down, thus giving you some breathing space.

The other use is the v trigger. This can only be used when the bar is full, and usually drains the bar on a timer or activates a special skill. Ryu's trigger is timed, temporarily powers up his hadokens and shoryukens, and allows him to charge hadokens (full charge will guard break). Nash teleports to the opponent, allowing him to extend a combo or turn the tides while under pressure (this consumes the entire bar). Necalli's trigger makes him allround better, and lasts for the rest of the round (his also means v reversals are no longer an option until the round ends).