How To Buy ETFs in FIdelity?

I usually buy mutual funds for my individual brokerage account. Very straight forward, I click buy and the dollar amount and that's it. I've been wanting to buy some ETFs (VOO, VTI, and VT specifically) for my Fidelity individual brokerage account. When I try to buy VTI, there is Market vs Limit and Shares vs Dollars. If I want to straight and simple buy $10,000 worth of VTI do I click Market or limit and do I click Shares or dollars? Thanks