I'm making 220k in 2018 and I want to contribute to try IRA! is this contribution deductible ?
Can I convert it to ROTH IRA back door ROth ira? How long I have to do so for 2018?
1) A Traditional IRA deduction is not limited by income unless you are covered by a retirement plan at work (usually indicated by box 13 on your W-2). If you are so covered then yiu can still make a non-deductible contribution.
2) A 2019 "Backdoor Roth" only works if your total 2019 year end value of all existing Traditional, SEP and SIMPLE IRA accounts that might exist is zero, otherwise any non-deductible basis must be prorated over the entire ending value and only a portion of the conversion would not be taxable.
3) You had until December 31, 2018 to do a 2018 Roth conversion. Any conversion in 2019 is a 2019 conversion reported next year in 2020.