Car seat frustrating question

What car seat to buy please post pictures what car seat should a five year old be in what about six year old

have been thinking about this why do five point harness cause decapitation internal. The seatbelt is supposed to keep child safe during a crash why did they make a seat belt so dangerous? Is the adult shoulder strap and lap seat belt safest?

Why do race car drivers use five point harness?

I am so confused I thought that you're supposed to forward face at four years old.

If you rear face where will child put their legs will they fit.

If children don't fit in the smaller convertible car seat like the purple black one is it time to get a bigger adjustable car seat with five point harness or start booster seat.

To forward face or rear face