Best way to arrange a session?

Game stores are usually open to people running games in their store if they have the space.

Cafes MIGHT be open to it, but remember, you're tying up one of their tables for four hours or so. It's usually not worth it to them, but if one does allow you to sit and play for that long, make sure everyone at the table orders something.

You might try the local library! Those are places open to the public, and often have rooms or quiet corners for events. Maybe a book store, but again, anyone coming should buy something.

As for running a group of strangers, have a 'session 0' for meeting, character building, and going over rules you may or may not be using. 

I have a group of DnD friends that has remained (relatively) the same for almost 2 years now. We play at my house on (almost always) the same day - Wednesday, at (almost always) the same time - 7pm - 11pm. This group is every other week, with the off weeks being a similar group that plays on Fridays, also 7pm -11pm. 

The advice above is great, especially the library. That also removes a monetary cost to DnD (as you can use the books, assuming they have them, while you are there!)

My advice is:

- Find DnD friends. Making friends into DnD friends is cool if doable, but not every friend is a DnD friend. Sometimes it just doesn't work out. No hard feelings.

- Set a predictable day and time to play. Spontaneous groups almost never last. 

- Start with a Session 0. This is where you discuss your wanted game types, rules used, create characters, etc etc etc.

- The 5e2024 DMG is good for new players and DMs, as it takes these sort of things into account more than before, but I also recommend "Return of The Lazy Dungeon Master" as well. Solid little handbook!