how do I join alpha skip ahead. currently stuck in Delta.

Depends in which insider group you are. Alpha skip ahead first, then, alfa, then delta and omega. For regular users in the same time.

That feature is only available to Alpha,Alpha skip aheads & Beta Insiders at the moment.

As you are in the Delta ring you will still need gold to play any games online.

You must be invited to become an Alpha Insider or Alpha Skip Ahead Insider, to do so You must Very active in Xbox, doing missions and report the bugs You see in the system, as much as You do this, so You Will be Very close to become an Alpha Insider. You
must be at least in Delta preview to become an Alpha Insider, but You Just need to be an Insider to be invited to become an Alpha Skip Ahead, but this one is very rare to be invited and there is a certain number of people to be invited, no more than that,
If You were not invited to be Alpha Skip Ahead certain time, so You must wait a Second chance when they Will invite New members.

Not all Insiders have access to not requiring gold for f2p games at the moment.Only Alpha/Alpha skip ahead & Beta rings are testing it.If you are not in any of those rings then you will still need a gold sub at the moment.

I have access im in the delta lvl and it talks about us testing it but it will not work on my Xbox and I’m on the current update for delta and I see the I have a Xbox network id

The "new" Edge is currently only available to Alpha Skip Ahead Insider preview members.

Insider issues are handled by Reddit Xbox Insiders forum. This forum is for General release OS issues.

Edit.. As of 22nd July "new" Edge is available to Alpha, Beta, Delta Insider previews so it is getting closer to a General release.