need help whit some cinematics that i want to make its like a want to put some guns on a table but i dont know how

There's a few options you could consider. In no part order:

1. Using a mod that adds those gun models as objects for use in the map editor. And then editing the map itself.

2. Dropping the guns on the ground, while standing on the table.

3. Using a vanilla "Plaque" to visibly store the guns, and then using the admin build mode (one of the Function keys while in Freecam) to hide the plaque under the table. Some mods may have alternatives to the Plaque.

4. Using a mod that adds those models as peaceable barricades.