I want to register a .man domain but I have no idea when its going to be available.
and is it possible to pre-register this domain name? when i search for it on namecheap or godaddy no .man domains come up.
You can take a look here. It seems to be updated periodically .
https://www.onlydomains.com/domains/new/launch-diary#launchDiary
Do not be fooled by anyone trying to sell you their services or by using third party information.
ICANN is in charge of accreditating new registries and opening new TLDs. This should be the only source you take as authoritative on this matter.
Go to http://gtldresult.icann.org/application-result/applicationstatus to track status of all current new gTLDs.
You can also use this other page: https://newgtlds.icann.org/en/program-status/sunrise-claims-periods to have dates (as communicated by the registries themselves) on their opening in progressive phases.
Do not get involved in any kind of pre-reservation/preorder scheme. There is nothing guaranteed there for the end users, so better wait from registries announcements when their TLD open.
As for .man
you can see on https://www.iana.org/domains/root/db/man.html that it went live (published in the root zone) around 2015-02-27. You can see its other dates at https://newgtlds.icann.org/en/program-status/sunrise-claims-periods/man but it is a "brand" TLD, so very restricted, as owned by a company for its single use. In short, you as an individual will never be able to buy a domain name there.
Adding up to all the answers, There is a way to get the release time notification of all new TLDs. Getting a reseller account at resellerclub or any other domain provider. You will be timely notified plus you will get great discounts.
https://www.name.com/preorder brought me to http://www.trademark-clearinghouse.com/gtld-calendar, which seems like it's probably real.
.man
listed there or in ICANN, so that may not be pending release at this time (or possibly in the future, despite what some sites might indicate).