When you first open the Halflings chapter, you'll start with unlocking the Spring Grove. From there you enter your first choice - Improved Trader, Irrigation Canal, or Halflings Farm.
Once you've finished researching the Spring Grove, start building it right away.
Next, you'll want to work on unlocking the Improved Trader. This way, you can work on getting it upgraded and producing Divine Seeds while you work your way through researching the Halflings Farm.
Unlocking the trader will set you back 125,000 Mana, and then you'll need another 100,000 to pay for the trader upgrade. While you work on gathering that and then waiting for the upgrade, start researching Irrigation Canal.
After the Canal, then work on unlocking the Halflings Farm.
Try to get a few built while you work on unlocking Agriculture, which you'll need in order to build the Grain Fields.
From there, your next journey might depend on your priorities, but based on the goods we can see are needed for which types of research, and the things we know about what it takes to make each of those goods, one logical path seems to be:
City Expansion 41
Orc Strategist Promotion
Squad Size upgrade
As we can see in the requirements for each research, the Divine Seeds requirement is high.
Depending on the level of your main hall, the number of provinces you have completed, the number of Ancient Wonders and at what levels you have, and how often you can collect from the trader, you will be able to collect anywhere from around 9,000 - 17,000 or more Divine Seeds a day.
You'll want to collect as often as possible from the trader to keep up with the Divine Seeds requirements.
Mana requirements don't get any easier from previous chapters, either. It will be important to maintain high mana production.
Further, be sure to plan your production and collection of the Grain Field resources well; Bread, which requires Wheat (from level 1 field) and Carrots (from level 2 field) will be needed through the end of the chapter.