Converting an e-bike is a simple task that only requires a few basic tools. Here is a quick list of what you should expect to need to convert a bike to e-bike.
Metric Allen keys
Many bike parts are held together by SHCS (Socket head cap screws) that require Allen keys to undo. Metric Allen keys are used on bikes, but you might encounter some e-bike kit that uses imperial somewhere.
While there are not many bolts on bikes these days, e-bike kits may require you tighten bolts. A crescent wrench can do in a pinch but is much more likely to strip bolts. Make sure to fully tighten a crescent wrench on the bolt before applying force. Bikes are generally metric bolts.
Crank puller and Bottom bracket removal tool
if installing a mid drive, generally the crank and bottom bracket must be removed and replaced. Many crank pullers and bottom bracket removal tools also require a large wrench to use. Not needed for hub motors.
Good for connecting wires. potentially also a soldering gun style for any extra thick wires that need to be soldered. You may be able to do without one by using certain crimp connectors and joins but its good to have.
Digital Multi meter
Required to diagnose any potential issues with the bike/battery.
Its best to get proper crimping tools as an improper crimp could leave you stranded on the side of the road or worse, cause damage to the wiring/bike when it overheats. I highly recommend a JST crimping tool for e-bikes as many of the connectors used on e-bikes are JST. If you wish to go with Anderson Powerpole connectors, an Anderson crimper would be highly recommended as well. If you use XT60 connectors you can solder them and don't need a crimper for them.
Often you will need to cut wires to length or apply different connectors. Scissors can do in a pinch but you are likely to damage them. Pliers with wire cutter sections are much better or wire strippers that include a cutter.
Often you will have to strip wires after cutting them to length or when replacing a connector. Wire strippers will help strip the wire properly without damaging it. don't use a knife or wire cutter for a stripper. Many strippers also include wire cutting functionality and may double as one.
Heat shrink or Electrical tape
You will need to insulate wires after soldering them together. it is also good to use heat shrink or electrical tape to strain relieve wires that go to connectors.
Zip ties are great to secure wiring to the frame of your bike. Electrical tape could also be used but zip ties tend to be cleaner looking. Velcro straps can also be used.