These are salon pieces, likely arrangements or fantasies on popular melodies of the era, designed for entertainment and showcasing pianistic skill. They would have featured virtuosic passages and perhaps borrowed melodic material.
Focus on bringing out the melodic line amidst elaborate accompaniment figures.
2 Paraphrases de salon (Op.70) is rated Henle level 5 of 9 — late intermediate repertoire, roughly ABRSM grades 6–7.
You should be comfortable at Henle level 5 — meaning you can already play level 4–5 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
2 Paraphrases de salon (Op.70) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.