I've gotten a good recomendation on lead-free, Kester SN 96. Leaded solders are surely going to disappear sooner or later, and I can't believe lead has any sonic positives , no matter how much silver is tossed in.
Do not, do not learn to solder on your kit. You can't determine a true, perfect, mil-spec solder joint by eyeballing it; especially depending on your eyesight/age. Mil-spec joints are inspected one-by-one by a qualified inspector under a low power microscope. You'll also need to know about flux removal, down to the 100% level; also inspected.
You'll need to know about matching iron tip temp to the solder you're using, and the care and feeding of iron tips.
Do not, do not learn to solder on your kit. You can't determine a true, perfect, mil-spec solder joint by eyeballing it; especially depending on your eyesight/age. Mil-spec joints are inspected one-by-one by a qualified inspector under a low power microscope. You'll also need to know about flux removal, down to the 100% level; also inspected.
You'll need to know about matching iron tip temp to the solder you're using, and the care and feeding of iron tips.