Gardening isn’t all that complicated. Plants need water, nutrients and sun. The chicken manure you have is great for a garden. If you have clean wood ashes, scatter them around. Timing when you plant is also important - too early, when the soil is cold may prevent germination, while planting too late may put plants into a dry spell. Above all, visit your garden for a few minutes each day to see if it needs some action like watering, weeding or bug remediation. Finally, keep your soil loose. Don’t over-till though.
BTW, I do not plow, till or do much weeding because I use a sand and mulch approach. It can sometimes be tricky.