It's a form of hosting service wherein the account owner can use his or her allotted hard drive space and bandwidth to host websites on behalf of third parties. The re-seller purchases the host's services in wholesale and then sells it to customers, possibly for a profit. Hope this helps.
The best is to upload the installation file to the directory you would want it to be installed through your control panel. Not that hard. You will just need some basic knowledge. hope this helps.
Never heard about them. Check if they are available 24x7 via email, chat or call support, also see if they offer money back guarantee for better security.
You should get the SPF and DKIM records from the mail provider, in your case that's Zoho, but this should be set where your DNS is hosted, and that's Host1.
When setting this up in your Advanced DNS zone editor, you should create two TXT records. You should also check with Host1 if they...