This is mostly if doing outdoor outings.
Dress in layers. If you find it cold, you can always add multiple pairs of gloves, socks, and scarves and take them off as you get hot. There are balaclava type things and long John’s available as well.
They sell little hot pockets you can activate and they stay warm for 2-3 hours or so, you can keep them in your gloves and boots. There are self heating gloves as well with batteries.
Keeping a thermos with a hot beverage helps as well.
Don’t get wet, this includes sweating a lot.
I’m not sure what the best course of action is but it is worrying behavior. Those are the biggest news communities. There are also two people who are moderators on both instance, if you were banned from both by the same person, that is quite problematic.