Here's a couple I have used:

Leonardo.Ai https://app.leonardo.ai/auth/login?callbackUrl=%2F There's free and paid versions. With free you'll find you have access to the basic settings and then there's other features which you need to pay for. There's also an image upscaler, motion and others. You get a certain amount of tokens to spend on image creation, which renew every 7 hours. Even in the basic package the resulys are very good

Bing Image Create is pretty good, you'll need a Microsoft account to use this. https://www.bing.com/images/create Lress control over the imnage creation than Leonardo>ai, but still good. Again you get a certain amount of tokens to spend every 24 hours (i think)

Midjourney is the industry leader, the quality is out of this world. Their free version finished a long time ago. It's accessed through discord