Portfolios
Building robots at home and including your efforts in a portfolio is a great starting point.
Vendor Certifications
Particularly in the old robotics industry, many vendors issue certifications in specific equipment.
That extends to useful adjacent industries, such as Autodesk Certifications or Unity Developers etc.
Community Colleges
In California, the Community Colleges have 1-2 year degrees in robotics and mechatronics..
Degree Institutions
Robotics is usually studied under MEng, EEng, Computer Science, but can also be found in Design, Psychology, Control Systems/Cybernetics, Cognitive Studies and Neuroscience.
MOOCs and Online Courses
Circuit Launch
Non linear engineering degrees without the cost. Circuit Launch provides education that is hands on and project based (includes online/virtual classes). Learn robotics by building and programming robots with peers. https://circuitlaunch.com