Add links to course material

Author: raiisac

content/tutorials/r_brms/index.md

@@ -8,7 +8,8 @@ tags: ["generalized linear regression", "brms", "r", "mixed models"]
 ---
 
 In the fall of 2023, a tutorial on Bayesian statistics with the **brms** packages was organised at INBO.
+Before you start the tutorial, please follow the instructions in [this R script]() to install brms properly.
 All course material can be found in Dutch and English on the following pages:
 
-- [English version](../../html/workshop_1_mcmc_en_brms_eng.html)
-- [Dutch version](../../html/workshop_1_mcmc_en_brms.html)
+- The [English tutorial](../../html/workshop_1_mcmc_en_brms_eng.html) with all [course material](https://inbo.github.io/tutorials/tutorials/r_brms/brms_eng) to test the examples yourself.
+- The [Dutch tutorial](../../html/workshop_1_mcmc_en_brms.html) with all [course material](https://inbo.github.io/tutorials/tutorials/r_brms/brms_nl) to test the examples yourself.