ubiquiti are decent, then look at mikrotix, then tplink.

depends, they usually have preconfigured the device so you plug it in and it works.

or you can get your own device and configure some settings for authentication etc.

other products and brands, could be netgear, but im a fan on tplink deco

1 run fibers

2 ethernet cable

3 p2p wireless bridge if a clear line of site

4 more powerful outdoor AP also if clear line of site