Yes, the do it yourself kits have most everything to effectively add refrigerant to your system. Only add refrigerant untill the site glass becomes "clear" indicating a full charge. With engine running and with ac compressor on. Rev engine to 1500-2000 rpms to simulate a full load condition. Do Not Overcharge!
Before adding ref. use a mixture of Water and Dawn dish detergent for a bubble leak detector. Brush bubbles on all connections, flanges, fittings, hose ends, etc.
Note, if you see any wet oil areas or oil dripping on the ac system lines, compressor, or fittings, there is a leak at that area. Hope this helps.
Dave
God Bless!