For easy use Tharians use the same time measurements as Earth. A 60min hr, 24hr day, 7day wk, 30 day mon, 365 yr, and so on, but remember Tharian society is very primitive.
You're not going to find watches or paper calendars. Some people track the days by marking on something. Some places have what they call Keepers of the Days. They're usually an elderly person or persons who can't do much else anymore, but despite whatever physical infirmities they have, these chosen elders are highly respected in the communities for the important job they do of keeping track of the days. They tell farmers when best to plant for a good harvest. They tell seasonal hunters the best times to hunt for the different game. They tell fisherman when the fish will migrate, and help others in their communities.
Distance is measured the same as Earth measurements. An inch, a foot, a mile.
You get the idea.
Weights and measures are in ounces, cups, pints, pounds. Why? I suck at metrics, and I'm not alone.
Tharians trade using a barter system. Something for something. They have no recognized standard of coin.
Seasons are simple. The cooler wet season and the hot dry season. If the Northern hemisphere is having their hot dry season, then the Southern hemisphere is having their cooler wet season. The two hemispheres' seasons are opposite most of the year. Except during a few weeks of the year when seasons are shifting.
The races here are humanoid and there is a list of the native races on this board. Read it. It's got a lot of helpful information.
If you want to introduce a new race, check with us first and have a description of it ready.