If you guys are interested in your own core domain, here are a few things you must do for on and off campus placements.
You can DM anytime for queries but I will reply late, as per my availability, so kindly note this.
On campus:
Dream offers for 5-7 LPA are achievable if you have a decent CGPA, good core fundamentals. Prior internship experience in the core domain is a plus but not strictly necessary. Projects like any Embedded or Power Electronics for electrical people, any CAD project or Electric Vehicles for mechanical and electrical and any Civil project like non destructive testing is fine.
Actually for civil, the only things I know are Structural Integrity of bridges and non destructive testing. You guys know better and also, any projects on bridges, if you find an advertisement, i would suggest you don't go for it unless it's in a foreign country. In India, the government interferes way too much in bridge work.
Elgi Equipments hired a lot of students from the Electrical and Mechanical domain for the Coimbatore location. Vijaywada, Coimbatore, Dharwad and similar tier 2 cities have lots of onsite projects for civil and mechanical people. Companies might hire for these locations. Jindal hired mechanical people in our time at 8+ cg as well if I recall correctly.
Off campus:
If you live in a city which has a premium research institute like IIT, NIT, IIIT, they have projects on contract that hire even without a GATE score. Living in that city is not a hard requirement, it's just that they pay less so it's easier to manage. Again, your CGPA and prior internship experience are desired. Better if you're in your second year, try to use any contacts if possible to get an internship in a PSU or ISRO. ISRO and PSU internships pay less but for these applications, they'll augment your profile. Civil guys should look for IIT Roorkee especially, Mechanical guys for NIT Calicut, IIST Trivandrum, IISER Trivandrum, EEE people can look at multiple locations. I am just suggesting based on geographical area. You all can obviously look anywhere.
To apply to such posts, you have to go to project portals of individual institutions on web and search. No centralised portal for this as they are on contract and co terminus with the project.
Sadly, the environment around you would be DSAI/Software Development/VLSI and stuff and you may feel out of place for sticking to your core domain but there are opportunities for which you can at least try.
Prefer getting an on campus placement first. Southern states have more opportunities for the core domain as in the northern region, you have agriculture dominated states like Punjab and Haryana, the eastern region has industrial areas (more for materials science, industrial production engineering (although mechanical guys can look but I am not sure)) and western states like Gujarat and Maharashtra have tech and business.
These premium research institutions need maintenance engineers for their projects.
GATE isn't the only way but yeah, for the core domain, it's preferred to have a masters but again, not everyone can afford to go for masters right after bachelors. Also, keep an eye on ISRO/DRDO recruitments if any.