Lookup value from one table from another

Hello,

i'm working on a project on Power BI but i'm still a beginner, so i need some help :)

i have table 1 :  "semaine"  and table 2 : "stock projeté"

Table 1 : Semaine

Table 2 : stock projeté

I have a relation 1 to many between Table 1 and 2. (key : ComonPeriod.Week)

--> i want to get the last day of week of my common period.Week of my table 1 from the column "last day of week" of table 2.

Thanks in advance :)