Hi rambo,
First of all, use SG3525 to generate pulses at 50kHz. Drive power MOSFETs with this and feed into ferrite transformer. Check the waveforms and add snubbers if necessary. After the voltage is stepped up, use rectifiers and caps to convert to clean DC. Then have another SG3525 and IR2110 running to drive an H-bridge at 50Hz. You should search for H-bridge, SG3525, IR2110 and similar things online and you will plenty of info. Then, you can post here and tell us where you are stuck.
@kabiru,
Hi. You should post here so that it benefits everyone on the forum.
Hope this helps.
Tahmid.