Studio Display and Dell Monitor connect to MacBook Pro

A Mac can only daisy-chain TWO displays on a Thunderbolt Dock/Device (not just USB-C dock/device).

The studio display is a ThunderBolt device, so it can only connect to a Dock with a ThunderBolt OUTPUT, as well as ThunderBolt input.

Although the CalDigit T3Plus Hub/Dock you cited meets these requirements, it is possible that results from that setup would be less than ideal, because the Studio display uses so much bandwidth on the ThunderBolt link to the computer. It could "crowd out" your other devices.

Best results may require you to connect the Studio Display directly on its own cable.

ALL the ThunderBolt cables required for this setup need to be the top-rated cables -- rated for top data rates and under 0.8 meters in length.

Hello haiv,

Welcome to Apple Support Communities!If we understand your post correctly, you want to know if you can connect 1 Dell and 1 Sturdio Display to your hub and will it work. We'd like to help!

Connect your Studio Display. Here’s how to get started. First, plug in your Studio Display to a wall outlet. Then plug in the included Thunderbolt cable to the Thunderbolt 3 port  on the back of the Studio Display, and connect it to your Mac or iPad. There’s no power button. Your display turns on automatically. To learn more, see the Apple Support article, Set up and use your Apple Studio Display.Connect accessories. Use the three USB-C ports on the back of your Studio Display to connect and charge accessories or to pair and charge wireless accessories such as a keyboard, mouse, and trackpad. See Connect an Apple wireless accessory with Mac in the macOS User Guide.Connect Studio Display

This article will be beneficial to you as well for setting and using Studio Display: Set up and use Apple Studio Display

Let us know if you have any questions. Thank you for using Apple Support Communities. Take care!