There are five types of H here, three different CH₂ units, a CH₃ unit, and the -OH unit, so we see five sets of peaks.
The most deshielded group (higher d / ppm, 3.63 ppm) is the C1 CH₂ unit with the electronegative oxygen atom attached. It has 2 H neighbour, so the n+1 rule means we see the 3 lines of a triplet.
As we move further from the effects of the oxygen atom, the chemical shifts decrease.
The C2 CH₂ unit has a total of 4 H neighbours (2 x CH₂) so the n+1 rule means that we see the 5 lines of a quintet.
The C3 CH₂ unit has a total of 5 H neighbours (1 x CH₂ + 1 x CH₃) so the n+1 rule means that we see the 6 lines of a sextet.
The CH₃ unit has 2 H neighbour, so the n+1 rule means we see the 3 lines of a triplet.
Hydroxyl protons (-OH) typically do not couple (due to exchange properties) so it appears here as a singlet.  They are also quite variable in their location (0.5-5 ppm). In this case about 2.25 ppm.
Integrals are in a 2:1:2:2:3 ratio.