If they were smoked the seeds may no longer be viable depending on how high the temperature was when they smoked it.
Typically, if you soak chili seeds in water overnight that will aid in germination.
Soaking them in water will also help you to determine which seeds are viable and which are not. Put the seeds in a cup of water and give the water a good stir. Wait about 30 seconds and discard all seeds that remain floating. The seeds that float are usually not viable. Some of the seeds that sink may also not be viable, but at least getting rid of the floating ones will narrow it down.
Chili de Arbol is a very common chili in grocery stores. I grew mine from seeds that I got from the grocery store. I bought dry Chili de Arbol and just took the seeds and planted them, so if the ones that your in-laws gave you don’t grow you can definitely get more from the grocery store and grow them.
With chilis I use a shotgun approach to growing them. I take like 50 seeds and soak them in water and then I plant them out in the garden or in a 3 gallon pot. After they germinate then I try to replant them in order to give them better spacing.
When I first started growing chilies I took a more deliberate approach and tried to baby the plants and do everything by the book, but that did not work out for me. For me growing chilies is a numbers game. Each plant will produce a bunch of fruit with a bunch of seeds and then you take those seeds and try to make them produce as many more plants as you can in hopes that the plants will survive and produce fruit. That is my advice to you.