added module/architecture change option

docs.it4i/cs/introduction.md

@@ -15,3 +15,24 @@ First stage of complementary systems implementation comprises of these partition
 - partition 5 – FPGA synthesis server
 
 ![](../img/cs1_1.png)
+
+## Modules and Architecture Availability
+
+Complementary systems list available modules automatically based on the detected architecture.
+
+However, you can load one of the three modules -- `aarch64`, `avx2`, and `avx512` --
+to reload the list of modules available for the respective architecture:
+
+```console
+[user@login.cs ~]$ ml architecture/aarch64
+
+  aarch64 modules + all modules
+
+[user@login.cs ~]$ ml architecture/avx2
+
+  avx2 modules + all modules
+
+[user@login.cs ~]$ ml architecture/avx512
+
+  avx512 modules + all modules
+```