If they just charged you after 7 years it may be beyond Washington's statute of limitations. Even so if a warrant was issued you need to get it recalled which may involve posting bail if you don't qualify for an OR (own recognizance) release. Either way you really need the help of an attorney in WA state.
There may be a warrant because the Prosecuting Attorney filed a criminal charge and when you didn't show up for your first court date, called the Arraignment, the Judge issued a warrant for your failure to appear. If there is a felony filed and a warrant has been issued, you need to talk to an attorney immediately in Seattle. A criminal defense attorney can help you set up a court date to get the warrant quashed, or recalled, and can help to resolve your case. You could also get some assistance from a Bail Bonding company that is familiar with the procedures in Seattle. You may be able to post a bond on the warrant amount. When the bond was posted with the Court, the Court would issue a new court date for you. You would have to be able to travel to Seattle to go to your next court date, or you would lose your bond and a new warrant would be issued for you.
If you do nothing, you could even be arrested on this warrant wherever you live. Some warrants are issued for multiple states or large geographic areas. They call these warrants "extraditable." For example, if you live in Oregon or California, and a Washington State warrant if issued for the West Coast, a person could be arrested on the Washington warrant in California. Then, they could have to wait in jail in California until Washington arranged transportation for them back to Washington. This process can take months.
It's in your best interest to try to take care of this outstanding issue. You should contact a Seattle criminal defense attorney as soon as possible. As for what will happen from your actual charge, that depends very much on what you are actually charged with. So, without more specific information, I cannot answer those questions for you.