how to clear log files

[Genti Hila]

hi,   I am running RedHat 8. My logfiles fill up once a week and take a lot of space in HDD. I just want to create a batch file to clean all the files once a week. Any idea how can i do that ?   I guess i will run it through anacron, but i do not know how to create the batch file. Any idea is appreciated.   Genti