وَإِذَا أَرَادَ الْإِحْرَامَ اغْتَسَلَ أَوْ تَوَضَّأَ، وَالْغُسْلُ أَفْضَلُ
Translation: When intending to enter iḥrām, one bathes or performs wuḍūʾ; bathing is preferable.
Ightasala means performing a bath and tawaḍḍaʾa making wuḍūʾ. The text prefers bathing, but does not make a bath a condition for the existence of iḥrām.
Personal preparation and legal entry into iḥrām are separate steps.