Mini PC N3150 (4C/4T, 2.08GHz Max) 8GB RAM 256GB SSD, 2X Type-c Mini Computer with 2x2K Display/WiFi 5/BT 4.2/RJ45 LAN/USB 3.0/6W TDP (1 PCs)

Play with a Pi Zero first. https://a.co/d/0g76ssNY You can spend $30-70 on a kit (depending on case/power supply needs), play with all that and maybe add some sensors/camera modules, and once you learn a bit apply the rest of the budget to something beefier. Or get a mini pc like this: https://a.co/d/0aVX4Zst Which will be quite a bit more capable running software (but not cool Pi-based sensor projects) stuff. You have enough budget to do both if you have a usb micro cable/power supply and an sd card lying around.