You will need to get
1. Batteries - in one of the following sizes 18350 18490 18500 18650 ( the 18 means how wide it is so these are 18 mm the next two numbers ie:35, 49, 50, 65 is the length in mm and the 0 on the end means cylindrical shape)
2. a charger for the batteries ie: Nitecore Intellicharger (this is my recommendation)
3. the K101 is normally threaded for 510 and ego both (similar to your ego twist battery)
4. optional - is a "kick" module to make it VW and have the safety options (will need to get 18500 batteries as a kick and an 18650 will not both fit
One thing to think of when going to a mechanical PV is when you put a fully charged battery (4.2v) the strength of the vape will be strong and as you use it and the battery discharges it will get progressively weaker (unless you have the kick module). You will also need to carry a multimeter with you to monitor the volts on the battery because you will not want to discharge the battery below 3.3 volts (unless you have a kick - it will shut down when you get to 3.3 volts)
My personal recommendation would be to get an MVP2 that is a self contained mod that does not need all the extra's to make it work and is available from $40 and up, and spend some time and money learning to do rebuildable atomizers (drippers, protank coils, or even a kayfun lite+, I just got one (tobeco clone, I know, I know) and it creates incredible taste and clouds of vapor with 2.1 ohm coil which will work on any regulated APV) before getting involved with a mechanical PV
hope this helps