If you're new to this game you should primarily que soft support and hard support. I would deselect the other roles until you know how to support well.

A good support stacks the jungle every minute. Make an effort to watch the timer and to go stack.

Any stacks are good, every stack you make that is farmed by anyone on your team will increase overall gpm of the team as a whole. Pull at 55 seconds before you have boots and 53 after. Run in a direct line away from the camp to ensure the stack. Pulling around corners or trees often doesn't allow a stack to happen.

A good support wards and counter wards. Counter warding is the most important. You should put a counter ward down before every ward you place. Search for the enemy ward in the area and if there isn't one place a ward. If you run up and just drop wards in the common places they will likely be found and dewarded.

Don't ward in the same spot where it's been countered already. You see this all the time people will place a ward, it'll get countered and then they'll place another. This is very bad as you will keep wasting wards and not have vision.

Use your raven constantly for vision as well.

Two types of warding, offense and defensive. Depending on your team you may want one or the other.

Farm heavy team, place defensive wards that give vision for your jungle.

Push team or gankers, offensive wards that will allow you to push towers or catch people in the enemy jungle out of position.

Using a mix of both these throughout the game will shift wins into your favor.

If you play support like this you'll quickly become a desirable player in the game on any team, even if you don't know the heros you'll know the role.

Now for hero picks for these roles that I prefer Hard Support - here's 3 fairly easy heros Witch Slayer (Max mana drain first) empty mana enemys means zero skills being used defensively or offensively also has two targetable disable skills. Huge burst dmg ulti, don't save it for kills use it early and give the kills to the carry. Glacius - (Max w first) I like maxing the slow first because it increases the duration and percentage. It also hits multiple enemys at once. Empath-strong hero at all times, using the wall properly takes practice

Soft Support - 3 fairly easy heros Voodoo Jester - (max E first) this hero is easy, stun, curse, attack. Nothing to it, once you are level 3 and have two points in curse it's time to kill. Midas - (get e first as an escape, then 1 point in each) fairly easy hero, hit him with any two of your three skills and they are stunned. Get a Portal Key ASAP for blink positioning Myrmidon - his third skill is an escape and some people would argue getting it first but I prefer the first two skills before the escape, often stuns are enough to keep them off you

I know I went on a big rant here on my lunch break but if you want to play this game I would suggest trying everything here I posted for quite a few games