Gallery program

please i need a program that can create gallery for my images.
(creates thumbnails and images with a specific size from the original image)
i have 300 images and i want to make gallery for them and i dont want to make them manually coz it takes more time.

i dont want to use photoshop.

so i need any other program that can make galeery with my entered size for thumbnails and also for large images

Iā€™d imagine you can find something in this list of 30 programs