3 ways to install windows 7, but first, you need a copy of the os itself.
1st: install using cdrom, insert lang sa cdrom then ifirst boot and cdrom para ung cd una basahin ng pc, kusa na ung setup just read the instruction.
2nd: USB, same as cdrom, bootable os sa cdrom, on how, watch utube.
3rd: lagay ka ng copy ng OS sa isang partition ng pc mo, example D:, kasi sa C: mo iinstall, extract mo lahat sa D: and run setup.exe (take note, sa 1st at 2nd step, my option ka mag format ng C:, pero dito sa step 3 wala )