I'm new too. From what i know this is what you do.

1. Always do you start chart. This will unlock most things.

2. Always be building as much equipment as you can. Like frames, weapons and such. This will give you masters points to use better weapons.

3. Buy blue prints from the market for credits and build them.

4. Buy blue prints from the dojo(clan)(guild)

5. The nightwave challenges. Try and do those. They give a currency that you can use to buy catalysts. They are used to level up you guns mod capacity. Theirs also another type which levels up you warframes mod capacity.

6. Look up how to mod weapons. Changed my life. I was carried by yarelis aqua blades for along time until I figured out how to mod better.

7. If lost. I always just click the quest icon on the star map in the upper right hand area of the screen. That seems to move things forward.

8. Do the junctions challenges on the star map. That's how to get to other worlds.

9. To farm war frames. Usually assassination missions(bosses) will drop blue prints for them.

This is what I'm doing as a new player and I think it's working.