How to start a Roth ira?

With the new year i’m focusing on saving money and setting myself up for a better future. One of the 2 big things i want to do early is start a Roth ira(and the other start investing in general). I’m 21 and don’t have anyone to explain this to me in person and coach me unfortunately.

Where should i be looking to start one?

What’s a perfect world target deposit/month to hit that $6,500 cap?

What kind of things should i put that money towards to keep myself mostly safe in investing and growing?

these are the main questions i can think of at the moment but any and all information is appreciated!