Is reading Surat Al-Baqarah in its entirety and continuously in one sitting every day for 7 days or more to achieve a specific matter considered an innovation (bid'ah), and is what is achieved thereafter a beautification by Satan?

There is no harm in using the recitation of the Qur'an as a means (tawassul) to fulfill a need. This is evidenced by the tawassul of the three men through their righteous deeds. However, it is preferable not to commit to reciting a specific surah continuously in one sitting, as this carries the risk of falling into additive innovations (bid'ah idafiyyah). One can recite whatever is easy from the Qur'an without adhering to a specific method, or perform two rak'ahs of prayer, or seek help through the narrated supplications.