Can you tell me how to remove ‘per month’ and t...

Just leave the spaces blank (do not remove because it will revert to default).

[vazz_pricing_table size="four columns"]
[vazz_pricing plan="Gold" cost="$29.99"  per="" button_text=""]

5 products
1 image per product
basic stats
non commercial
[/vazz_pricing]
[/vazz_pricing_table]

PS: Pls, don’t forget to use text editor mode in wordpress if you copy the code from here