POT lights play an important role in beauty of your house and also give more value for your house if you are selling it. Morover LED pot lights saves your money on Hydro bill as well. All pot lights we use are LED with energy star

Where should and what kind of pot lights we should install??

You can install pot lights in living room, family room, hall way, kitchen, dining area, bedroom and even in washrooms (special pot lights for dump/ moister location).
If there is insulation in ceiling then pot light should be IC rated if there is no insulation then it can be Non-IC.
Pot lights gives you even light throughout the area where pot lights are installed and also looks nice if pot lights are installed properly with symmetry and equal distance.
Also you can highlight some particular area you want like Niche, Paintings and family pictures.
For indoor pot lights beam angle should be 90 degree or greater for more light
Shape wise it can be regular round or square trim, slim panel type round and square trim

In colour selection of trim you can get white, black and brush nickel.

while for bulb colour you can get Warm white(3000k) or cool white (6000k)
Outdoor Pot Lights

For outdoor pot lights it should highlight brick, stucco or stone. It should never be on top of window or glass door which can bother you in night time when lights are on.
For outdoor pot light beam angle could be 35, 60 or 90degree

35 degree angle will be more focused and where 90degree will be more spread lightType your paragraph here.