mailbox full so here is my answer:
you can absolutely use the same computer! and same wifi! just not at the same time since you will likely only be on 1 IP at a time without getting too advanced
so for example, you do all your botting, playing, whatever on your main account on your main wifi IP address and no VPN or proxy or anything... then when you are done, turn on your VPN and bot your shells as much as you want! the reason for this is: if your bots get caught, they can get banned but neopets will have no way of knowing your main account is associated with them because they were never on the same IP!
as far as VPNs go... there are sooooooo many!! some I think even offer free promotional trials. I personally pay for PIA (Private Internet Access) - I believe it was around 40 dollars for 12 months of service and you can switch between over 20 IP addresses all over the world!
I see trees of green........ red roses too / I see em bloom..... for me and for you / And I think to myself.... what a wonderful world.
mail box full