what should that mean in English? Could you translate it, please?

Ridiculam fabulam participes ...

Sex menses, cum primum placuit primum Latinam ego scio hominem de linguis alienis, et quibus Latina difficilior putavi fore. Inquit 'quid dicis? Spanish facilis "Putabat Latina erat adamasset fuit dicens Spanish!

how i understood it/ interpreted it:

you shall participate in this humorous/ridiculous story...

six months, since i know (got to know) the first person who likes Latin out of foreign languages, and i thought, that Latin will be more difficult than those. He/She said, "What do you say? Spanish is easy" He/She was thinking, (when) Latin was, he/she would have become fond, (but) he/she has been speaking Spanish.

[meaning: two people, who like Latin ("I" and "he"), met. it could be possible that the "I" speaks its mind first and then it's only "him" speaking and thinking.  "He"(/she) was thinking that when there was Latin, he(/she) would have become fond of it, but now he(/she) is speaking Spanish, so there will be becoming fond of Latin]

suggestion:

Ridiculam fabulam participes ...

Sex menses, cum (primum) cui placuit Latinam primum (ego) scio hominem de linguis alienis, et quibus Latinam difficiliorem putavi esse (fore). Inquit "quid dicis? Hispanicum (Hispanica lingua) facilis  est." Putabat, cum Latina (lingua) fuit, (eam) adamasset. (quod sic) fuit, (is) loquens Hispanice!