When I rejected work in a lab

The first time to Mrs. Mirtha called me forto work in his lab, i donI didn’t think it was good, so aI say not,id that may be in 3 months, but iI would start my personal proyject so, but that was a lie.

Later to seSix months later, they called me again, in and this time we are talking about termns and conditions, foras at this moment my personal proyject is not working like igoing ahead so I think so I'mI’ll accept the work.

The first time to Mrs. Mirtha called me forto work in hiser lab, iI dont think goodidn't want to, so aI sayid not, may be in 3 months, but i. But I was starting my personal proyject so that was a lie.

(1) You're writing about something that happened in the past, so the past tense ("called", "didn't", "said", "was starting") is expected.
(2) The phrase is "call to (do something)".
(3) Since Mrs. Mirtha is female, it should be "her" and not "his".
(4) "I didn't think [it was] good" isn't something we really say in such a context. You can consider "I didn't want to".
(5) "Maybe" is one word.
(6) I split the sentence into two; I think it flows better this way, compared to being one long sentence.

Later to seSix months later, they called me again, in this time we awere talking about termns and conditions, for. At this moment my personal proyject was not working like i thinkas I thought (it would) so I'm accepted the work.

(1) The phrase is "X months later".
(2) Again, the past tense ("called", "thought", "accepted") is expected.
(3) We don't say "in this time". The phrase is just "this time".
(4) The phrase is "at this moment".
(5) Alternatively: "my personal project was not going as I thought it would" or "my personal project was not going as I'd imagined".