When I was young and had little cash to start a new garden the key for me was to select two tomatoes, one cucumber, one sweet pepper, one egg plant. I made sure they were able to grow well in my area. I also tried to select those that had the least disease and insect issues. Finally, I made sure the were not F1 hybrides, they were at least F5 or heirloom. So when I planted and got something to grow I would save seed. Then next year I would have those seeds which last years if saved properly and I would add a couple new ones. This allowed me to build up very useful seeds and to slowly build up my garden.
I do not know your level of experience but it sounds like you are starting a new garden. I learned the hardway many many decades ago that a few well tended varieties will yeild alot more than many poorly provided for plants.
So with a brand new garden I personally would not spend much money on seeds this year. I would just grow a few varieties. Where I would put my effort is in collecting any free compostable material you can get your hands on.
Things like lawn clippings, leaves, wood chips, etc. I would make creating a
compost pile a number one activity for this year.