Hi, @ulemsee, I'm also a novice like you as I started earlier this year. Onions are part of what I am doing. My advice is that input from agricultural professionals such as extension workers from the ministry of agriculture or amiran etc is invaluable and if you can get such contacts in your area they can really help. They will guide you on every step of the crop cycle.
Before starting out the following would be great to do
-Budgetting. Like for any venture make a comprehensive budget with allowance for emergencies.
-Soil testing. From this you will get a comprehensive report and advice on the amount of manure and fertilizer to use on the farm. If there are diseases/pests in the soil you may also be required to fumigate before planting.
-Market research. Research where and how you will sell your harvest before you plant. Plant as per the market demands.
-It is good to house the farmhand. Getting the right employee was a challenge I initially faced as my first employee was lazy and eventually absconded work causing me a major setback but I luckily got another who is much more reliable.
Now, about getting a licence to pump water from the river... well, I am next to a river and I have a pump (everyone else around there has a pump too) but I am not aware of licences being required in that area. I hope to hear more about that from other contributors even as I consult around about it.