You can SSH into your VPS by using a client such as Termius or PuTTY and the login details that were sent to you via email.
Yes, you can upgrade your vps hosting package at any time.
You can set up your own nameservers if you want. However, if you don't know how to or don't plan to, just use ns1 and ns2.
The password is what you set before purchasing the server. We also send a copy of it via email, and you can change it in the panel.
We offer a refund back to your original payment method within 48 hours within the purchase date and 7 days for account credits. However Dedicated machines are final purchases and can not be refunded.
We have locations in both Germany (EU) and Canada (NA).