Convert all 401k investments to a target date fund?

Im 42 years old and finally decided to invest more time on preparing for retirement. I spoke with an agent at fidelity who told me that I should sell my other investments and put them all into my target 2040 fund, and at most only invest 5% into Kroger, which is currently 26.77% of my investments.

I don’t mind liquidating everything else, but Kroger stock has given me my the highest return with a current value of $46k with a cost basis of $25.8k, and also pays a dividend that I reinvest. My current portfolio value is $172k which I recently switched my contributions to Roth contributions.

Also, should I convert my past traditional 401k contributions to Roth, or just invest continue to make new investments as Roth 401k investments going forward?

Any advice would be appreciated, thanks!

Current investments:

U.S. all cap equity 30.48%

Kroger stock 27.88%

Retirement date 2040 16.02%

Retirement date 2045 14.04%

U.S. bond index 12.69%