re: Any recommendations on what to invest in for hydrogen?

I like and own stock in Shell (SHEL) and Equinor (EQNR), but hydrogen is not their main business. They are energy companies in general.

Other companies that deal with hydrogen energy and are on my watch-list (but do not own) are Iberdrola (IBDRY), Linde (LIN) and L'Air Liquide (AIQUY).

Although, for good or bad, all of these are non-US companies and some people may not want that. Take with a heavy grain of salt.