Added context, I am an independent contractor who just entered grad school. I have 22k in loans at 4.3 interest and I expect to graduate with about 20k more in loans at the same rate. Right now, my loans aren’t accruing interest so I’m considering opening up a retirement fund.

With the solo 401k, in addition to the compounding interest I think I could benefit from the tax deduction on my contributions as tax rates for independent contractors are high. As I understand it, I could instead use the Roth option and pay the taxes later but there is a chance I get a regular job in addition to my independent contracting in 10-20 years so my assumption is the deduction would help me more now.

I am also a little unclear on the nature of 401ks and how they relate to bonds and stocks. As I understand it, one can invest through a 401k. Is that correct? Otherwise does it make sense to invest in something like a mutual fund or etf independent of a retirement account?

All that said, I could take the simple route and just pay off my loans before they start accruing interest again.

Thanks for any help you can provide! I’m pretty new to all of this.