Most probably a scam because a project without a team is purely greed and no plan at all. Creating your own website is good but if you’re not good enough on that I suggest to talk with a team, plan with a team and release the project with a team. Private sale usually partnered with a bigger investors, they will look for more genuine project for sure and if you’re not good enough, you’ll not be on the list.
Some people only do Telegram private sale I've seen now, they basically purchase the groups and emails, mass auto invites from those groups and walla,,, you have a group full of people you know were in other private sales. Exactly like email groups for newsletters,,, same model different media.