I have been doing my own nails since pre lockdown
When I first started with gels, I was having the same issues as yourself
Reason being I didn't have a bloody clue, bought some cheap old rubbish of the net and away I went
Doing your own gels is easy enough, as long as you get educated in how to use them
A few people I follow - Kirsty Meakin and Nailcareer education - both are really good at explaining every step and the why's and wherefores
Always use the lamp produced to the range of gels you intend to purchase
Try to find a professional range - Kirsty does one now although she used to work to Naio Nails - and they sell to the home user
Do educate yourself on the dangers of gels. You get an allergy through misuse, the allergy is for life and it can affect dental treatment and even hip replacements moving forward
You can also buy Hema free gel ranges which are better for you, less chance of an allergy but not promised to be of use after an allergy has arisen