I only use LLMs as a substitute for stackexchange, and sometimes to write boilerplate code. The free chat provided by deepseek works very well for me, and I've never encountered any usage limits. V3 / R1 are mostly sufficient. When I need something better (not very often), I use Claude's free tier.

If you really need another model / a custom interface, it's better to use openrouter: deposit $10 and you get 1000 free queries/day across all free models. That $10 will be good for a few months, at the very least.