Roth IRA, Target date index fund investing?

Hello Can I pls ask your opinion regarding how I invest in my roth IRA under fidelity, I have automatic ETF and it’s automatically invest to FSKAX. I’m confuse if that’s a target index fund. Thank you so much for your time.

FSKAX is a total US Stock market index fund. It’s great, but not fully diversified and reallocating like a target date index fund. There are ticker symbols for Fidelity target date index funds at the bottom of this article: