Can a navy seal participate in an exchange program with the sas or sbs?

Yes. A Navy Seal was attached to the SBS patrol present at the Qala-i-jangh uprising in Afghanistan.

Special Forces of the UK & US engage in regular joint training, and personnel exchanges are commonplace - certainly, in the 1970s there were numerous SEALs at the SBS base in Poole, Dorset: I met them when staying with my godfather, who was in the SBS. Incidentally, my godfather had a number of American medals, awarded during the 1960s for "actions of an unspecified nature" (he wouldn't tell!), but almost certainly, I think, earned whilst serving with SEAL teams in Vietnam...

The SAS and US Special Forces have had a regular NCO & Officer exchange programme since at least the early 1960s (two notable examples were Charlie Beckwith, RIP, who saw active service with the SAS in Malaya, and later founded "Delta Force", & Richard Meadows, RIP, who married a British woman, and was so well regarded/ popular that the CO of 22 SAS tried to recruit him permanently!); Frank Collins of 22 SAS (who was the youngest member of the team which assaulted the Iranian Embassy, 1980 - now, sadly, also deceased) so enjoyed his exchange with "Delta" that he nearly "went American" (but for his wife he would have done), and was thereafter known in the SAS Regt as "Frank the Yank"!

So, yes, it's quite common for US Navy SEALs, US Army SOF etc to participate in exchange programmes with their British equivalents, and - as noted above - these units work very closely together in A'stan, and elsewhere.