I want opinions

I sold a home. I bought some things that retain their value.

I have about 340k right now.

Im 50. No debt. No credit. I need to establish credit with a cash secured credit card. Ive also been told to get a Fiduciary Adviser.
No car. ..Don't really want one either. I plan on spending 2500 on an accountant this year to do my taxes. I called H&R Block and they were a joke

I inherited a home after I took care of my mom.
I just got a job. (knock on wood)

I keep hearing about compounding. The Warren Buffet way.
Im ok with renting studio apartments.

I might buy a couple more things but my plan is to get in to the index fund after the bubble bursts. Ive setup a Charles Shwabe account. Im getting ready to do it. I feel the market it a little nuts right now.

They say the hardest part is saving the first 100k. Or a fool and his money is lucky to get together in the first place. All true.

right now I have everything in HYSA. 4.2 percent.

Can you get money out the index fund without fees if needed? I realize that defeats the purpose of compounding but you never know.

Im just asking what others would do.

I don't have much in Social security built up. I did mostly under the table work in a rural area.
Im open to all advice. Thanks!