You don’t need the BEST soldering iron kit to get started, but I don’t recommend using one of those “On the Field” soldering irons that are powered by a Lipo battery.
Invest at least $50 dollars in a desktop soldering iron with adjustable temperature. This $40 one still going strong after 5 years in the industry, just had to replace the tips
Go with a 60/40 solder, this type of solder is easy to handle and last for multiple builds / repairs.
Having a clean iron tip is key! I recommend using a brass wire cleaner instead of a sponge that typically comes with soldering kits. Clean the tip before each application.