how to change pagination to first page in Velo on a wix table

Since you are already working with DATASETs, it should be an easy task…
https://www.wix.com/velo/reference/wix-dataset/dataset/nextpage
https://www.wix.com/velo/reference/wix-dataset/dataset/previouspage

Also you have the ability to check if a previous or next page existing…
https://www.wix.com/velo/reference/wix-dataset/dataset/hasnextpage
https://www.wix.com/velo/reference/wix-dataset/dataset/haspreviouspage

You do not switch the pages on table, instead you are switching them on your dataset and the table just show-up the results.