Despite this word ending with ‘er’, it is an anglicism used by snowboarders, skateboarders… and just means ‘to practice their activity’.

It is most of the time pronounced with a strong French accent: /ʁajde/ (courtesy of @jlliagre).

Usage example: "Tu viens rider avec nous cette après-midi?"

Hors le contexte de la question, il existe un verbe rider qui signifie former des rides, soit sur la peau à cause de la vieillesse, soit sur d’autres surfaces, par exemple à cause du vent sur l’eau.

Here ride is the English verb "to ride" used as is in French.

Je ride means "I ride", possibly a motocycle or it is just a metaphor showing he is "easy riding" the road (of success), i.e. going ahead.

There are other similar metaphors like:

la concu j’la vois dans le rétro (concu = concurrence)

I see the competition in the rear view mirror, i.e. I’m well ahead competition.

Je fais du rodéo is referring to rodéos urbains "urban rodeos" by quad or motorcycle (wheeling, drifting and the likes). The Wikipedia definition translates to:

Downtown riding of two-wheelers or quad bikes as a dangerous and noisy practice on unsuitable terrain.