The old gunsmithing books I mentioned ,such as Dunlap and Baker,would be a very good place to start.They talk a great deal about screwdrivers,chisels,files,etc,along with a great deal of other shop knowledge.
There are ref books of firearms disassembly/assembly.
One thing about guns is the cosmetic factor...different than mechanic work.
A speck of sand on a bench can really ruin your day if you slide a color case hardened Hi-Wall receiver over it.One little extra nibble with a chisel inletting a lock leaves a gap you will see forever.
I really like a good 10x loupe with about a 1 in focal length.
A calculator,solar,that will do trig.Paper and a pencil to plan and sketch.
A six in Browne and Sharpe or Starrett scale,flexible,satin chrome,with 1/10th graduations on one of the scales.
A tube of prussian blue.Some 12 in lengths of feeler stock about .025 thick to make scrapers.
If you lack a mill,you may get a drill press.If you do,get a Palmgren or other modest quality X -Y vise or table and a few center drills.Try for a vintage quality drill press like an old Delta Rockwell.Spindle must run true.Check it with a pin and indicator.
I do not own a Dremel tool.Try a 65,000 rpm or so air pencil grinder.And a Foredom with the low speed on the backside.
You need a proper coffee cup.Very important.
It has many uses.Its where the answers come from.Sometimes thinking harder does not work.Have a cup and let the answers come to you.
Its also good when things aren't going quite right or you are pushing a little hard...just stop before you screw something up,have a cup,chill.Then you won't have a new problem to fix.
Keep it enjoyable.
One path you might try,get a Dixie catalogue.Maybe Ned Roberts"The Muzzle Loading Cap Lock Rifle"
Order a Siler Lock kit,and a Muzzle loader barrel..maybe a .36 or .40.Make a squirrel rifle.There is a Foxfire book where Herchel House builds a poor boy rifle.
Its not real hard,simple tools,but you will drill and tap,torch heat treat,inlet,file,fit,shape and finish...
Fun to shoot when you get done.