It is a complete nonsense. When you have Deutrium-Deutrium fusion, there is neutron emission. It will not change regarding the purpose of your doing so. The fact that it requires D2-D2 fusion to generate the Helium-3 fuel renders this project futile. It goes back to step 1 again. It is still neutronic fusion because you need the Helium-3 fuel.

Public Wifi of course is not safe. Avoid using them at all cost. Public chargers are easy. There are so many cheap to hell USB cables that do not have data wire. No data is possible for those cheapo USB cables. Buy one and use it for public chargers. It is physically not possible to pass any data and thus is not hackable. Those cut corner function down USB cables are godsend for hacking prevention using public charges.