So, I’m going to make a couple of assumptions here based on what you are saying, and those are going to guide my responses. I’m assuming that you are:
- Sticking to high sec
- Going mainly solo
- Still getting your feet under yourself
- Not looking to going a larger corp or alliance
If any of those are incorrect, the advice will change 
Yep, ganking happens but it’s not terribly hard to avoid if you follow some basic rules.
- Train up shield skills for mining ships
- Don’t go AFK- stay at the keyboard and pay attention to who warps in to the system or belt
- Fit your ships for tank rather than yield. When you get to bigger ships, that means Procurers and Skiffs
- Give known gankers their corps and alliances “Terrible Standings” so you can more easily see when they pop up
- Avoid known nasty areas (i.e. Udaema, Halaima, etc.)
Follow those basic rules and you’ll generally be OK.
This is hard to answer because there are so many variables and it can take a long time to get up the skills and investments (BPs) to make really profitable stuff. T1 production is going to be tough to make a profit on and T2 requires a pretty robust supply chain due to the additional materials that you will need. Here’s a thread with some general advice for moving on in mining and production:
Finding a niche is hard, but my advice is to watch the local market for things that are consumed quickly or used commonly in your area and build what you can that might support that.
Diversify, at least until you find your niche. Take some stuff to major hubs, take some to regional hubs, try to sell some locally. Things will move at different rates in each of those locations and they have different challenges (volume vs. the -.1 ISK game at big hubs). Try it all and see what works for you and how you like to manage things.