Can I be prosecuted for purchasing SARMS online?

That appears to be a really bad idea. https://www.crnusa.org/SARMs

You should retain an attorney or attorneys to help you clear up the warrants, one way or another. Warrants don't go away by themselves.

Do I have to show up in court for being the respondent of a restraining order?

If you don't appear after being given proper notice of a court proceeding, the court can give the petitioner what she wants.

Will the state of Oregon expadite me from the state of Washington for absconding ?

See https://app.leg.wa.gov/RCW/default.aspx?cite=10.88 and: https://www.oregonlegislature.gov/bills_laws/ors/ors133.html

I’m 18 and she’s 15?

See...

If my petty theft misdemeanor is expunged do I still have to say I have it on a job application?

See https://www.courts.wa.gov/newsinfo/index.cfm?fa=newsinfo.displayContent&theFile=content/guideToCrimHistoryRecords.

Can a person earn good time & use it to reduce the portion of their sentence designated to an enhancement on the charged crime?

The Department of Corrections has a certain amount of latitude in administering prison sentences. See...

Can non custodial parent at modification of child support hearing. Request both of us to take drug test.

See CR 35 http://www.courts.wa.gov/court_rules/?fa=court_rules.display&group=sup&set=CR&ruleid=supcr35

How easy would it be to get full custody

It appears he already does have all the responsibility for parenting the children. To get a court ordered parenting plan, he would have to file...

Receiving state aid for dependent not currently living with me, but I'm giving financial support for?

If you really feel guilty, you can pay the money back.